Social media marketing strategy: definition, conceptualization, taxonomy, validation, and future agenda

Although social media use is gaining increasing importance as a component of firms’ portfolio of strategies, scant research has systematically consolidated and extended knowledge on social media marketing strategies (SMMSs). To fill this research gap, we first define SMMS, using social media and marketing strategy dimensions. This is followed by a conceptualization of the developmental process of SMMSs, which comprises four major components, namely drivers, inputs, throughputs, and outputs. Next, we propose a taxonomy that classifies SMMSs into four types according to their strategic maturity level: social commerce strategy, social content strategy, social monitoring strategy, and social CRM strategy. We subsequently validate this taxonomy of SMMSs using information derived from prior empirical studies, as well with data collected from in-depth interviews and a quantitive survey among social media marketing managers. Finally, we suggest fruitful directions for future research based on input received from scholars specializing in the field.


Introduction
The past decade has witnessed the development of complex, multifarious, and intensified interactions between firms and their customers through social media usage. On the one hand, firms are taking advantage of social media platforms to expand geographic reach to buyers (Gao et al. 2018), bolster brand evaluations (Naylor et al. 2012), and build closer connections with customers (Rapp et al. 2013). On the other hand, customers are increasingly empowered by social media and taking control of the marketing communication process, and they are becoming creators, collaborators, and commentators of messages (Hamilton et al. 2016). As the role of social media has gradually evolved from a single marketing tool to that of a marketing intelligence source (in which firms can observe, analyze, and predict customer behaviors), it has become increasingly imperative for marketers to strategically use and leverage social media to achieve competitive advantage and superior performance (Lamberton and Stephen 2016).
Despite widespread understanding among marketers of the need to engage customers on social media platforms, relatively few firms have properly strategized their social media appearance and involvement (Choi and Thoeni 2016;Griffiths and Mclean 2015). Rather, for most companies, the ongoing challenge is not to initiate social media campaigns, but to combine social media with their marketing strategy to engage customers in order to build valuable and long-term relationships with them (Lamberton and Stephen 2016;Schultz and Peltier 2013). However, despite the vast opportunities social media offer to companies, there is no clear definition or comprehensive framework to guide the integration of social media with marketing strategies, to gain a rigorous understanding of the nature and role of social media marketing strategies (SMMSs) (Effing and Spil 2016).
Although some reviews focusing on the social media phenomenon are available (e.g., Lamberton and Stephen 2016;Salo 2017), to date, an integrative evaluation effort focusing on the strategic marketing perspective of social media is missing. This is partly because the social media literature largely derives elements from widely disparate fields, such as marketing, management, consumer psychology, and computer science (Aral et al. 2013). Moreover, research on SMMSs mainly covers very specific, isolated, and scattered aspects, which creates confusion and limits understanding of the subject (Lamberton and Stephen 2016). Furthermore, research deals only tangentially with a conceptualization, operationalization, and categorization of SMMSs, which limits theory advancement and practice development (Tafesse and Wien 2018).
To address these problems, and also to respond to repeated pleas from scholars in the field (e.g., Aral et al. 2013;Guesalaga 2016;Moorman and Day 2016;Schultz and Peltier 2013 to identify appropriate strategies to leverage social media in today's changing marketing landscape, we aim to systematically consolidate and extend the knowledge accumulated from previous research on SMMSs. Specifically, our objectives are fivefold: (1) to clearly define SMMS by blending issues derived from the social media and marketing strategy literature streams; (2) to conceptualize the process of developing SMMSs and provide a theoretical understanding of its constituent parts; (3) to provide a taxonomy of SMMSs according to their level of strategic maturity; (4) to validate the practical value of this taxonomy using information derived from previous empirical studies, as well as from primary data collection among social media marketing managers; and (5) to develop an agenda for promising areas of future research on the subject.
Our study makes three major contributions to the social media marketing literature. First, it offers a definition and a conceptualization of SMMS that help alleviate definitional deficiency and increase conceptual clarity on the subject. By focusing on the role of social connectedness and interactions in resource integration, we stress the importance of transforming social media interactions and networks into marketing resources to help achieve specific strategic goals for the firm. In this regard, we provide theoretical justification of social media from a strategic marketing perspective. Second, using customer engagement as an overarching theory, we develop a model conceptualizing the SMMS developmental process. Through an analysis of each component of this process, we emphasize the role of insights from both firms and customers to better understand the dynamics of SMMS formulation. We also suggest certain theories to specifically explain the particular role played by each of these components in developing sound SMMSs. Third, we propose a taxonomy of SMMSs based on their level of strategic maturity that can serve as the basis for developing specific marketing strategy concepts and measurement scales within a social media context. We also expect this taxonomy to provide social media marketing practitioners with fruitful insights on why to select and how to use a particular SMMS in order to achieve superior marketing results.

Defining SMMS
Although researchers have often used the term "social media marketing strategy" in their studies (e.g., Choi and Thoeni 2016;Kumar et al. 2013;Zhang et al. 2017), they have yet to propose a clear definition. Despite the introduction of several close terms in the past, including "social media strategy" (Aral et al. 2013;Effing and Spil 2016), "online marketing strategy" (Micu et al. 2017), and "strategic social media marketing" (Felix et al. 2017), these either fail to take into consideration the different functions/features of social media or neglect key marketing strategy issues. What is therefore required is an all-encompassing definition of SMMS that will capture two fundamental elements-namely, social media and marketing strategy. Table 1 draws a comparison between social media and marketing strategy on five dimensions (i.e., core, orientation, resource, purpose, and premise) and presents the resulting profile of SMMS.

Social media
In a marketing context, social media are considered platforms on which people build networks and share information and/or sentiments (Kaplan and Haenlein 2010). With their distinctive nature of being "dynamic, interconnected, egalitarian, and interactive organisms" (Peters et al. 2013, p. 281), social media have generated three fundamental shifts in the marketplace. First, social media enable firms and customers to connect in ways that were not possible in the past. Such connectedness is empowered by various platforms, such as social networking sites (e.g., Facebook), microblogging sites (e.g., Twitter), and content communities (e.g., YouTube), that allow social networks to build from shared interests and values (Kaplan and Haenlein 2010). In this regard, "social connectedness" has also been termed as "social ties" (e.g., Muller and Peres 2019;Quinton and Wilson 2016), and the strength and span of these ties determine whether they are strong or weak (Granovetter 1973). Prior studies have shown that tie strength is an important determinant of customer referral behaviors (e.g., Verlegh et al. 2013).
Second, social media have transformed the way firms and customers interact and influence each other. Social interaction involves "actions," whether through communications or passive observations, that influence others' choices and consumption behaviors (Chen et al. 2011). Nair et al. (2010 labeled such social interactions as "word-of-mouth (WOM) effect" or "contagion effects." Muller and Peres (2019) argue that social interactions rely strongly on the social network structure and provide firms with measurable value (also referred to as "social equity"). In social media studies, researchers have long recognized the importance of social influence in affecting consumer decisions, and recent studies have shown that people's connection patterns and the strength of social ties can signify the intensity of social interactions (e.g., Aral and Walker 2014;Katona et al. 2011).
Third, the proliferation of social media data has made it increasingly possible for companies to better manage customer relationships and enhance decision making in business (Libai et al. 2010). Social media data, together with other digital data, are widely characterized by the 3Vs (i.e., volume, variety, and velocity), which refer to the vast quantity of data, various sources of data, and expansive real-time data (Alharthi et al. 2017). A huge amount of social media data derived from different venues (e.g., social networks, blogs, forums) and in various formats (e.g., text, video, image) can now be easily extracted and usefully exploited with the aid of modern information technologies . Thus, social media data can serve as an important source of customer analysis, market research, and crowdsourcing of new ideas, while capturing and creating value through social media data represents the development of a new strategic resource that can improve marketing outcomes (Gnizy 2019).

Marketing strategy
According to Varadarajan (2010), a marketing strategy consists of an integrated set of decisions that helps the firm make critical choices regarding marketing activities in selected markets and segments, with the aim to create, communicate, and deliver value to customers in exchange for accomplishing its specific financial, market, and other objectives. According to the resource-based view of the firm (Barney 1991), organizational resources (e.g., financial, human, physical, informational, relational) help firms enhance their marketing strategies, achieve sustainable competitive advantage, and gain better performance. These resources can be either tangible or intangible and can be transformed into higher-order resources (i.e., competencies and capabilities), enabling the delivery of superior value to targeted buyers (Hunt and Morgan 1995;Teece and Pisano 1994).
Different marketing strategies can be arranged on a continuum, on which transaction marketing strategy and relationship marketing strategy represent its two ends, while in between are various mixed marketing strategies (Grönroos 1991). Webster (1992) notes that long-standing customer relationships should be at the core of marketing strategy, because customer interaction and engagement can be developed into valuable relational resources (Hunt et al. 2006). Morgan and Hunt (1999) also claim that firms capitalizing on long-term and trustworthy customer relationships can help design value-enhancing marketing strategies that will subsequently generate competitive advantages and lead to superior performance.

SMMS
From a strategic marketing perspective, social media interaction entails a process that allows not only firms, but also customers to exchange resources. For example, Hollebeek et al. (2019) assert that customers can devote operant (e.g., knowledge) and operand (e.g., equipment) resources while interacting with firms. Importantly, Gummesson and Mele (2010) argue that interactions occur not simply in dyads, but also between multiple actors within a network, underscoring the critical role of network interaction in resource integration. Notably, customer-tocustomer interactions are also essential, especially for the higher level of engagement behaviors (Fehrer et al. 2018).
Thus, social media interconnectedness and interactions (i.e., between firm-customer and between customer- To interact and connect To achieve competitive advantage To generate, integrate, and reconfigure social media resources to achieve specific marketing objectives Premise To recognize different customer motivations of social media brand-related activities To enhance long-lasting customer relationships by delivering superior value To capitalize on social media interactions and customer engagement so as to generate marketing resources customer) can be considered strategic resources, which can be further converted into marketing capabilities (Morgan and Hunt 1999). A case in point is social customer relationship management (CRM) capabilities, in which the firm cultivates the competency to use information generated from social media interactions to identify and develop loyal customers (Trainor et al. 2014). With the expanding role of social media from a single communication tool to one of gaining customer and market knowledge, marketers can strategically develop distinct resources from social media based on extant organizational resources and capabilities. Drawing on the previous argumentation, we define SMMS as an organization's integrated pattern of activities that, based on a careful assessment of customers' motivations for brand-related social media use and the undertaking of deliberate engagement initiatives, transform social media connectedness (networks) and interactions (influences) into valuable strategic means to achieve desirable marketing outcomes. This definition is parsimonious because it captures the uniqueness of the social media phenomenon, takes into consideration the fundamental premises of marketing strategy, and clearly defines the scope of activities pertaining to SMMS.
Although the underlying roots of traditional marketing strategy and SMMS are similar, the two strategies have three distinctive differences: (1) as opposed to the traditional approach, which pays peripheral attention to the heterogeneity of motivations driving customer engagement, SMMS emphasizes that social media users must be motivated on intellectual, social, cultural, or other grounds to engage with firms (and perhaps more importantly with other customers) (Peters et al. 2013;Venkatesan 2017); (2) the consequences of SMMS are jointly decided by the firm and its customers (rather than by individual actors' behaviors), and it is only when the firm and its customers interact and build relationships that social media technological platforms become real resource integrators (Singaraju et al. 2016;Stewart and Pavlou 2002); and (3) while customer value in traditional marketing strategies is narrowly defined to solely capture purchase behavior through customer lifetime value, in the case of SMMS, this value is expressed through customer engagement, comprising both direct (e.g., customer purchases) and indirect (e.g., product referrals to other customers) contributions to the value of the firm (Kumar and Pansari 2016;Venkatesan 2017).

Conceptualizing the process of developing SMMSs
The conceptualization of the process of developing SMMSs is anchored on customer engagement theory, which posits that firms need to take deliberate initiatives to motivate and empower customers to maximize their engagement value and yield superior marketing results (Harmeling et al. 2017). Kumar et al. (2010) distinguish between four different dimensions of customer engagement value, namely customer lifetime value, customer referral value, customer influence value, and customer knowledge value. This metric has provided a new approach for customer valuation, which can help marketers to make more effective and efficient strategic decisions that enable long-term value contributions to customers. In a social media context, this customer engagement value enables firms to capitalize on crucial customer resources (i.e., network assets, persuasion capital, knowledge stores, and creativity), of which the leverage can provide firms with a sustainable competitive advantage (Harmeling et al. 2017).
Customer engagement theory highlights the importance of understanding customer motivations as a prerequisite for the firm to develop effective SMMSs, because heterogeneous customer motivations resulting from different attitudes and attachments can influence their social media behaviors and inevitably SMMS outcomes (Venkatesan 2017). It also stresses the role of inputs from both firm (i.e., social media engagement initiatives) and customers (i.e., social media behaviors), as well as the importance of different degrees of interactivity and interconnectedness in yielding sound marketing outcomes (Harmeling et al. 2017). Pansari and Kumar et al. (2017) argue that firms can benefit from such customer engagement in both tangible (e.g., higher revenues, market share, profits) and intangible (e.g., feedbacks or new ideas that help to product/ service development) ways.
Based on consumer engagement theory, we therefore conceive the process of developing an SMMS as consisting of four interlocking parts: (1) drivers, that is, the firm's social media marketing objectives and the customers' social media use motivations; (2) inputs, that is, the firm's social media engagement initiatives and the customers' social media behaviors; (3) throughputs, that is, the way the firm connects and interacts with customers to exchange resources and satisfy needs; and (4) outputs, that is, the resulting customer engagement outcome. Figure 1 shows this developmental process of SMMS, while Table 2 indicates the specific theoretical underpinnings of each part comprising this process.

Drivers
Firms' social media marketing objectives Though operating in a similar context, SMMSs may differ depending on the firm's strategic objectives (Varadarajan 2010). According to resource dependence theory (Pfeffer and Salancik 1978), the firm's social media marketing objectives can be justified by the need to acquire external resources (which do not exist internally) that will help it accommodate the challenges of environmental contingencies. In a social media context, customers can serve as providers of resources, which can take several forms (Harmeling et al. 2017). Felix et al. (2017) distinguish between proactive and reactive social media marketing objectives, which can differ by the type of market targeted (e.g., B2B vs. B2C) and firm size. While for proactive objectives, firms use social media to increase brand awareness, generate online traffic, and stimulate sales, in the case of reactive objectives, the emphasis is on monitoring and analyzing customer activities.
Customers' social media use motivations Social media use motivations refer to various incentives that drive people's selection and use of specific social media (Muntinga et al. 2011). The existence of these motivations is theoretically grounded on uses and gratifications theory (Katz et al. 1973), which maintains that consumers are actively and selectively involved in media usage to gratify their psychological and social needs. In a social media context, motivations can range from utilitarian and hedonic purposes (e.g., incentives, entertainment) to relational reasons (e.g., identification, brand connection) (Rohm et al. 2013). Muntinga et al. (2011) also categorize consumer-brand social media interactions as motivated primarily by entertainment, information, remuneration, personal identity, social interaction, and empowerment.

Inputs
Firms' social media engagement initiatives Firms take initiatives to motivate and engage customers so that they can make voluntary contributions in return (Harmeling et al. 2017;Pansari and Kumar 2017). These firm actions can also be theoretically explained by resource dependence theory (Pfeffer and Salancik 1978), which argues that firms need to take initiatives to encourage customers to interact with them, to generate useful autonomous contributions that will alleviate resource shortages. Harmeling et al. (2017) identify two primary forms of a firm's marketing initiatives to engage customers using social media: task-based and experiential. While task-based engagement initiatives encourage customer engagement behaviors with structured tasks (e.g., writing a review) and usually take place in the early stages of the firm's  Table 2 Theoretical anchoring of components constituting the process of developing social media marketing strategies social media marketing efforts, experiential engagement initiatives employ experiential events (e.g., multisensory events) to intrinsically motivate customer engagement and foster emotional attachment. Thus, firm engagement initiatives can be viewed as a continuum, where at one end, the firm uses monetary rewards to engage customers and, at the other end, the firm proactively works to deliver effective experiential incentives to motivate customer engagement.
Customers' social media behaviors The use of social media by customers yields different behavioral manifestations, ranging from passive (e.g., observing) to active (e.g., co-creation) ). These customer social media behaviors can be either positive (e.g., sharing) or negative (e.g., create negative content), depending on customers' attitudes and information processes during interactions (Dolan et al. 2016). Harmeling et al. (2017) characterize customers with positive behaviors as "pseudo marketers" because they contribute to firms' marketing functions using their own resources, while those with negative behaviors may turn firmcreated "hashtags" into "bashtags." Drawing on uses and gratifications theory, Muntinga et al. (2011) also categorize customers' brand-related behaviors in social media into three groups: consuming (e.g., reading a brand's posts), contributing (e.g., rating products), and creating (e.g., publishing brand-related content).

Throughputs
Within the context of social media, both social connectedness and social interaction can be explained by social exchange theory, which proposes that social interactions are exchanges through which two parties acquire benefits (Blau 1964). Based on this theory, such a social exchange involves a sequence of interactions between firms and customers that are usually interdependent and contingent on others' actions, with the goal to generate sound relationships (Cropanzano and Mitchell 2005). Thus, successful exchanges can advance interpersonal connections (referred to as social exchange relationships) with beneficial effects for the interacting parties (Cropanzano and Mitchell 2005).
Social connectedness Social connectedness indicates the number of ties an individual has on social networks (Goldenberg et al. 2009), while Kumar et al. (2010) define connectedness with additional dimensions, including the number of connections, the strength of the connections, and the location in the network. Social media research suggests that connectedness has a significant impact on social influence. For example, Hinz et al. (2011) show that the use of "hubs" (highly connected people) in viral marketing campaigns can be eight times more successful than strategies using less connected people. Verlegh et al. (2013) also examine the impact of tie strength on making referrals in social media and confirm that people tend to interpret ambiguous information received from strong ties positively, but negatively when this information comes from weak ties.
Social interaction Social interaction within a social media context is quite complex, as it represents multidirectional and interconnected information flows, rather than a pure firm monologue . This is because, on the one hand, social media have empowered customers to be equal actors in firm-customer interactions through sharing, gaming, expressing, and networking, while, on the other hand, customer-customer interactions have emerged as a growing market force, as customers can influence each other with regard to their attitudinal or behavioral changes (Peters et al. 2013). Chen et al. (2011) identify two types of social interactions-namely, opinion-or preference-based interactions (e.g., WOM) and action-or behavior-based interactions (e.g., observational learning)-with each requiring different strategic actions to be taken. Chahine and Malhotra (2018) also show that two-way (multiway) interaction strategies that allow reciprocity result in higher market reactions and more positive relationships.

Outputs
Customer engagement The outputs are expressed in terms of customer engagement, which reflects the outcome of firmcustomer (as well as customer-customer) connectedness and interaction in social media (Harmeling et al. 2017). 1 It is essentially a reflection of "the intensity of an individual's participation in and connection with an organization's offerings and/or organizational activities, which either the customer or the firm initiates" (Vivek et al. 2012, p. 127). The more customers connect and interact with the firm's activities, the higher is the level of customer engagement created (Kumar and Pansari 2016;Malthouse et al. 2013) and the higher the customer's value addition to the firm (Pansari and Kumar 2017). Although the theoretical explanation of the notion of customer engagement has attracted a great deal of debate among scholars in the field, research (e.g., Brodie et al. 2011;Hollebeek et al. 2019;Kumar et al. 2019) has also begun adopting the service-dominant (S-D) logic (Vargo and Lusch 2004) because of its emphasis on customers' interactive and value co-creation experiences in market relationships. Following the service-dominant (S-D) logic, Hollebeek et al.
(2019) stress the role of customer resource integration, customer knowledge sharing, and learning as foundational in the customer engagement process, which can subsequently lead to customer individual/interpersonal operant resource development and co-creation.
Despite its pivotal role in social media marketing, extant literature has not yet attained agreement on the specific measurement of customer engagement. For example, Muntinga et al. (2011) conceptualize customer engagement in social media as comprising three stages: consuming (e.g., following, viewing content), contributing (e.g., rating, commenting), and creating (e.g., user-generated content). Maslowska et al. (2016) propose three levels of customer engagement behaviors: observing (e.g., reading content), participating (e.g., commenting on a post), and co-creating (e.g., partaking in product development). Moreover, Kumar et al. (2010) distinguish between transactional (i.e., buying the product) and nontransactional (i.e., sharing, commenting, referring, influencing) behaviors of customer engagement derived from social media connectedness and interactions.

Taxonomy of SMMSs
The distinctive differences among firms engaged in social media marketing with regard to their strategic objectives, organizational resources and capabilities, and focal industries and market structures, imply that there must also be differences in the SMMSs pursued. In this section, we first explain the criteria classifying SMMSs into different groups and then provide an analysis of their content.

Classification criteria of SMMSs
Drawing from the extant literature, we propose three important criteria that can be used to distinguish SMMSs: the nature of the firm's strategic social media objectives with regard to using social media, the direction of interactions taking place between the firm and the customers, and the level of customer engagement achieved.
Strategic social media objectives refer to the specific organizational goals to be achieved by implementing SMMSs (Choi and Thoeni 2016;Felix et al. 2017). These can range from transactional to relational-oriented, depending on the strategist's mental models of business-customer interactions (Rydén et al. 2015). Different mental models have a distinctive impact on managers' social media sense-making, which is responsible for framing the specific role defined by social media in their marketing activities (Rydén et al. 2015). Rydén et al. (2015) identify four types of social media marketing objectives with four different mental models that can guide SMMSs -namely, to promote and sell (i.e., businessto-customers), to connect and collaborate (i.e., business-with-customers), to listen and learn (i.e., business-from-customers), and to empower and engage (i.e., business-for-customers).
The direction of the social media interactions can take three different forms. These include (1) one-way interaction, that is, traditional one-way communication in which the firm disseminates content (e.g., advertising) on social media and customers passively observe and react (Hoffman and Thomas 1996); (2) two-way interaction, that is, reciprocal and interactive communication with exchanges on social media, which can be further distinguished into firm-initiated interaction (in which the firm takes the initiative to begin the conversation) and customer participation (by liking, sharing, or commenting on the content) and customer-initiated interaction (in which the customer is the initiator of conversations by inquiring, giving feedback, or even posting negative comments about the firm, while the firm listens and responds to customer voice) (Van Noort and Willemsen 2012); and (3) collaborative interaction, that is, the highest level of interaction that builds on frequent and reciprocal activities in which both the firm and the customer have the power to influence each other (Joshi 2009).
With regard to the level of customer engagement, as noted previously, this heavily depends on the strength of connections and the intensity of interactions between the firm and the customers in social media, comprising both transactional and nontransactional elements (Kumar et al. 2010). Because customer engagement is the result of a dynamic and iterative process, which makes specifying the exact stage from participating to producing rather difficult (Brodie et al. 2011), we adopt the approach proposed by various scholars in the field (e.g., Dolan et al. 2016;Malthouse et al. 2013) to view this as a continuum, ranging from very low levels of engagement (e.g., "liking" a page) to very high levels of engagement (e.g., co-creation).

Types of SMMSs
With these three classificatory criteria, we can identify four distinct SMMSs, representing increasing levels of strategic maturity: social commerce strategy, social content strategy, social monitoring strategy, and social CRM strategy. 2 Fig. 2 illustrates this taxonomy for SMMSs, Table 3 shows the differences between these four strategies, while Appendix Table 6 provides real company examples using these strategies. In the following, we analyze each of these SMMSs by explaining their nature and characteristics, the particular role played by social media, and the specific organizational capabilities required for their adoption.
Social commerce strategy Social commerce strategy refers to the "exchange-related activities that occur in, or are influenced by, an individual's social network in computer-mediated social environments, whereby the activities correspond to the need recognition, pre-purchase, purchase, and post-purchase stages of a focal exchange" (Yadav et al. 2013, p. 312). Rydén et al. (2015, p. 6) claim that this way of using social media is not to create conversation and/or engagement; rather, the reasons for "the initial contact and the end purpose are to sell." Similarly, Malthouse et al. (2013) argue that social media promotional activities do not actively engage customers because they do not make full use of the interactive role of social media. Thus, social commerce strategy can be considered as the least mature SMMS because it has a mainly transactional nature and is preoccupied with short-term goal-oriented activities (Grönroos 1994). It is essentially a one-way communication strategy intended to attract customers in the short run.
In this strategy, social media are claimed to be the new selling tool that has changed the way buyers and sellers interact (Marshall et al. 2012). They offer a new opportunity for sellers to obtain customer information and make the initial interaction with the customer more efficient (Rodriguez et al. 2012). Meanwhile, firms are also increasingly using social media as promising outlets for promotional/advertising purposes given their global reach (e.g., Dao et al. 2014;Zhang and Mao 2016), especially to the millennial generation (Confos and Davis 2016). However, as firms' social media activities in this strategy are more transactional-oriented, customers tend to be passive and reactive. Customers contribute transactional value through purchases, but without a higher level of engagement. Therefore, we conclude that, within the context of this strategy, customers exchange their monetary resources (e.g., purchases) with the firm's promotional offerings.
To better develop this strategy, Guesalaga (2016) highlights the need to understand the drivers of using social media in the selling process. He further stresses that personal commitment plays a crucial role in using social media as selling tools. Similarly, Järvinen and Taiminen (2016) urged for an integration of marketing with the sales department in order to gain better insights from social media marketing efforts. The importance of synergistic effects between social media and traditional media (e.g., press mentions, television, in-store promotions) has also been stressed in supporting social commerce activities (e.g., Jayson et al. 2018;Stephen and Galak 2012). Thus, selling capabilities are crucial in this strategy, requiring the possession of adequate selling skills and the use of multiple selling channels to synergize social media effects.
Social content strategy Social content strategy refers to "the creation and distribution of educational and/or compelling content in multiple formats to attract and/or retain customers" (Pulizzi and Barrett 2009, p. 8). Thus, this type of SMMS aims to create and deliver timely and valuable content based on customer needs, rather than promoting products (Järvinen and Taiminen 2016). By attracting audiences with valuable content, the increase in customer engagement may ultimately boost product/service sales (Malthouse et al. 2013). Holliman and Rowley (2014, p. 269) also claim that content marketing is a customer-centric strategy and describe the value of content as "being useful, relevant, compelling, and timely." Therefore, this strategy provides a two-way communication in which firms take Fig. 2 Taxonomy of social media marketing strategies the initiative to deliver useful content and customers react positively to this content. The basic premises of this strategy are to create brand awareness and popularity through content virality, stimulate customer interactions, and spread positive WOM (De Vries et al. 2012;Swani et al. 2017).
Social media in this strategy have been widely used as communication tools for branding and WOM purposes (Holliman and Rowley 2014;Libai et al. 2013). On the one hand, firms generate content by their own efforts on social media (termed as 'firm-generated' or 'marker-generated' content) to actively engage consumers. On the other hand, firms encourage customers to generate the content (termed as 'user-generated' content) through the power of customer-to-customer interactions, as in the case of exchanging comments and sharing the brand-related content. In this way, firms provide valuable content in exchange for customer-owned resources, such as network assets and persuasion capital, to generate positive WOM and achieve a sustainable trusted brand status.
To pursue a social content strategy, firms build on capabilities focusing on how content is designed and presented (expressed in the form of a social message strategy) and how content is disseminated (expressed in the form of a seeding strategy). Thus, understanding customer engagement motivations and social media interactive characteristics is central to designing valuable content and facilitating customer interactions that would help to stimulate content sharing among customers (Malthouse et al. 2013). Designing compelling and valuable content in order to transform passive social media observers into active participants and collaborators is also key capability required by firms adopting this strategy (Holliman and Rowley 2014). Empowering customers and letting them speak for the brand is another way to engage customers with brands. Therefore, in this strategy, marketing communication capabilities are important for effective marketing content development and dissemination.
Social monitoring strategy Social monitoring strategy refers to "a listening and response process through which marketers themselves become engaged" (Barger et al. 2016, p. 278). In contrast with social content strategy, which is more of a "push" communication approach with content delivered, social monitoring strategy requires the firm's active involvement in the whole communication process (from content delivery to customer response) (Barger et al. 2016). More specifically, social monitoring strategy is not only to observe and analyze the behaviors of customers in social media (Lamberton and Stephen 2016), but also to actively search for and respond to customer online needs and complaints (Van Noort and Willemsen 2012). A social monitoring strategy is thus characterized by a two-way communication process, in which the initiation comes from customers who comment and behave on social media, while the company takes advantage of customer behavior data to listen, learn, and react to its customers. Thus, the key objective of this strategy is to enhance customer satisfaction and cultivate stronger relationships with customers through ongoing social media listening and responding. With today's abundance of attitudinal and behavioral data, firms adopting this strategy use social media platforms as "tools" or "windows" to listen to customer voices and gain important market insights to support their marketing decisions . Moreover, Carlson et al. (2018) argue that firms can take advantage of social media data to identify innovation opportunities and facilitate the innovation process. Hence, social media monitoring enables firms to assess consumers' reactions, evaluate the prosperity of social media marketing initiatives, and allocate resources to different types of conversations and customer groups (Homburg et al. 2015). In other words, customers in this strategy are expected to be active in social media interactions, providing instantaneous and real-time feedback. This has in a way helped product development and experience improvements with resource inputs from customers' knowledge stores.
Social monitoring strategy emphasizes the importance of carefully listening and responding to social media activities to have a better understanding of customer needs, gain critical market insights, and build stronger customer relationships (e.g., Timoshenko and Hauser 2019). It therefore requires firms to be actively involved in the whole communication process with customers, as customer engagement is not dependent on rewards, but is developed through the ongoing reciprocity between the firm and its customers (Barger et al. 2016). Thus, organizational capabilities, such as marketing sensing through effective information acquisition, interpretation and responding, are essential for the successful implementation of this strategy. More specifically, monitoring and text analysis techniques are needed to gather and capture social media data rapidly (Schweidel and Moe 2014). Noting the damage caused by electronic negative word of mouth (e-NWOM) on social media, firms adopting this strategy also require special capabilities to appropriately respond to customer online complaints and requests (Kim et al. 2016).
Social CRM strategy Among the four SMMSs identified, social CRM strategy is characterized by the highest degree of strategic maturity, because it reflects "a philosophy and a business strategy supported by a technology platform, business rules, processes, and social characteristics, designed to engage the customer in a collaborative conversation in order to provide mutually beneficial value in a trusted and transparent business environment" (Greenberg 2009, p. 34). The concept of social CRM is designed to combine the benefits derived from both the social media dimension (e.g., customer engagement) and the CRM dimension (e.g., customer retention) (Malthouse et al. 2013). In contrast with the traditional CRM approach, which assumes that customers are passive and only contribute to customer life value, social CRM strategy emphasizes the active role of customers who are empowered by social media and can make a contribution to multiple forms of value (Kumar et al. 2010). In brief, a social CRM strategy is a form of collaborative interaction, including firm-customer, inter-organizational, and intercustomer interactions, that are intended to engage and empower customers, so as to build mutually beneficial relationships with the firm and lead to superior performance.
Social media have become powerful enablers of CRM (Choudhury and Harrigan 2014). For example, Charoensukmongkol and Sasatanun (2017) argue that the integration of social media and CRM provides a possibility for firms to segment their customers based on similar characteristics, and can customize marketing offerings to the specific preferences of individual customers. With social CRM strategy, firms can enhance the likelihood of customer engagement through one-to-one social media interactions. Customers at this stage are collaborative and interactive in value creation, such as voluntarily providing innovative ideas and collaborating with brands (Jaakkola and Alexander 2014). Hence, besides resource like network assets, persuasion capital, and knowledge stores, engaged customers also contribute their creativity resource for value co-creation.
Social CRM capability is "a firm-level capability and refers to a firm's competency in generating, integrating, and responding to information obtained from customer interactions that are facilitated by social media technologies" (Trainor et al. 2014, p. 271). Therefore, firms should be extremely creative to combine social media data with its CRM system, as well as to link the massive social media data on customer activities to other data sources (e.g., customer service records) to generate better customer-learning and innovation opportunities (Choudhury and Harrigan 2014; Moe and Schweidel 2017). Social CRM strategy also emphasizes the significance of reciprocal information sharing and collaborations that are supported by the firm's culture and commitment, operational resources, and cross-functional cooperation (Malthouse et al. 2013;Schultz and Peltier 2013). To sum up, social CRM capabilities, organizational learning capabilities connected with relationship management and innovation are essential prerequisites to building an effective social CRM strategy.

Validation of proposed SMMSs
Using the previously developed classification of SMMSs (i.e., social commerce strategy, social content strategy, social monitoring strategy, and social CRM strategy) as a basis, we reviewed the pertinent literature to collate useful knowledge supporting the content of each of these strategies. Table 4 provides a summary of the key empirical insights derived from the extant studies reviewed, together with resulting managerial lessons. Social commerce strategy • Social media as selling, promotion, and advertising platform has a positive impact on customer purchase intentions and financial performance.
► Use social media carefully and sensibly for the purpose of selling and promoting products/services and this in turn will help increase your customer base and generate more sales. • Interactiveness, informativeness, entertainment, and credibility of social media advertising positively affect customer behavior and purchase intention.
► Make sure that your social media ads are exciting, informative, and believable to gain customer trust and stimulate interest to buy your products/services. • Social networks and interactions have a strong influence on social media commerce.
► Leverage social networks and interactions to motivate and engage customers to make purchases through, for example, monetization of social networks. • Social media and traditional marketing have synergistic impact on company's sales.
► While using social media as marketing tools, it is advisable to combine them with traditional marketing tools to achieve superior results. • Perceived privacy risk and the intrusiveness of social media advertising negatively impact on customer attitudes and purchase intentions.
► In using social media ads, be sensitive and respectful to issues related to customer privacy and intrusiveness to avoid negative feelings by customers.

Social content strategy
Content popularity and vitality are influenced by: • Social message strategy (e.g., brand names, functional and emotional appeals, vividness and interactivity, inspirational knowledge and trending topics, content-user fit) ► To attract customer attention and spread favorable news make your messages lively and attractive, focus on contemporary issues, adjust the content to target customers' interests, and stress the strengths of your products/services. • Seeding strategy (e.g., use of highly connected people, different characteristics of relationships, influential) ► Increase virality of your messages in social media by seeking the assistance of influential individuals who have an extensive network, are opinion leaders, and have the ability to attract and easily connect with other people. • Context (e.g., B2B, B2C), product characteristics (e.g., low-utilitarian and high-utilitarian), organizational processes and IT tools ► Be aware that the popularity impact of your social media content becomes stronger when you have proper design processes in place and use the right automation tools. Your viral marketing approach should be also carefully adapted according to your specific product characteristics.

Social monitoring strategy
• Social monitoring strategy emphasizes the importance of social listening and responding to customer needs.
► Listen carefully to the discussions and comments made by customers in social media, identify specific needs and preferences from these, and respond accordingly and quickly with the right company offering. • Social media have become "listening tools" to observe and analyze customers and firms should adopt different techniques to analyze social media data.
► In addition to traditional marketing research methods, make sure you also invest adequate time and effort in using social media as a means to gather useful, reliable, and fresh information about customer attitudes/behaviors. • Firms' active interactions with customers influence customer behaviors.
► Actively interacting with customers using social media should be a never-ending process, which, with proper monitoring and right incentives, can help favorably influence customer behavior. • Different types of responses (e.g., volume and speed), voices (e.g., human and ► To effectively stimulate positive customer reactions in social media, it is important to To validate the practical usefulness of our proposed classificatory framework of SMMSs, we first conducted a series of in-depth interviews with 15 social media marketing practitioners, who had their own firm/brand accounts on social media platforms, at least one year of social media marketing experience, and at least three years' experience in their current organization (see Web Appendix 1). Interviewees represented companies located in China (8 companies), Finland (5 companies), and Sweden (2 companies) and involved in a variety of industries (e.g., digital tech, tourism, food, sport). All interviews were based on a specially designed guide (which was sent to participants in advance to prepare them for the interview) and were audiotaped and subsequently transcribed verbatim (see Web Appendix 2).
The main findings of this qualitative study are the following: (1) social media are mainly used as a key marketing channel to achieve business objectives, which, however, differentiates in terms of product-market type, organization size, and managerial mindset; (2) distinct differences exist across organizations in terms of their social media initiatives to deliver content, generate reactions, and develop social CRM; (3) there are marked variations in customer engagement levels across participant firms, resulting from the adoption of different SMMSs; (4) the firm's propensity to use a specific SMMSs is enhanced by infrastructures, systems, and technologies that help to actively search, access, and integrate data from different sources, as well as facilitate the sharing and coordination of activities with customers; and (5) the adoption of a specific SMMS does not follow a sequential pattern in terms of strategic maturity development, but rather, depends on the firm's strategic objectives, its willingness to commit the required resources, and the deployment of appropriate organizational capabilities.
To further confirm the existence of differences in profile characteristics among the four types of SMMSs, we conducted an electronic survey among a sample of 52 U.S. social media marketing managers who were randomly selected. For this purpose, we designed a structured questionnaire incorporating the key parameters related to SMMSs, namely firms' strategic objectives, firms' engagement initiatives, customers' social media behaviors, social media resources and capabilities required, direction of interactions, and customer engagement levels (see Web Appendix 3).
Specifically, we found that: (1) each of the four SMMSs emphasize different types of strategic objectives, ranging from promoting and selling, in the case of social commerce strategy, to empowering and engaging in social CRM strategy; (2) experiential engagement initiatives geared to customer respond swiftly and frequently, use different voices/tones, and adapt styles to fit specifically each communication context. • Firm response strategies (e.g., public apology, problem-solving responses, and accommodative strategies) were found useful in dealing with negative e-WOM.
► Although negative e-WOM should be avoided by all means, in case this appears you can use an array of tools, ranging from corporate acknowledgment and public apology to recovery actions and compensation. Social CRM strategy • Customer engagement and social CRM capabilities affect the core of social CRM strategy, which positively affects competitive advantage and performance.
► Put continuous emphasis on engaging your customers in social media in a systematic and consistent way, because this is likely to yield favorable financial and non-financial results. • Customer resource integration, customer knowledge sharing, and learning are the key foundational customer engagement processes.
► Take initiatives to enhance the engagement of customers in social media by integrating resources with them, exchanging knowledge, and learning as much as possible about their characteristics, attitudes, and behaviors. • Although the firm's customer engagement initiatives play an important role in motivating customers' voluntary contributions, their effectiveness may vary across market contexts.
► Be wary of encouraging customers to use social media postings (especially for luxury and identity-relevant products), because this may harm customers' perceptions of premium brand image. • Social CRM capability is a firm-level capability that helps generate, integrate, and respond to social media information and enhance customer engagement.
► Develop specific capabilities (e.g., those anchored on operational excellence, information technology, and specific employee skills/knowledge) to systematically collect, analyze, and act on data derived from interactions with customers in social media. engagement were more evident at the advanced level, as opposed to the lower level strategies; (3) passive customer social media behaviors were more characteristic of the social commerce strategy, while more active customer behaviors were observed in the case of social CRM strategy; (4) the more advanced the maturity of the SMMS employed, the higher the level customer engagement, as well as the higher requirements in terms of organizational resources and specialized capabilities; and (5) one-way interaction was associated more with social commerce strategy, two-way interaction was more evident in the social content strategy and the social monitoring strategy, and collaborative interaction was a dominant feature in the social CRM strategy (see Web Appendix 4).

Future research directions
While the extant research offers insightful information and increased knowledge on SMMSs, there is still plenty of room to expand this field of research with other issues, especially given the rapidly changing developments in social media marketing practice. To gain a more accurate picture about the future of research on the subject, we sought the opinions of academic experts in the field through an electronically conducted survey among authors of academic journal articles written on the subject. We specifically asked them: (1) to suggest the three most important areas that research on SMMSs should focus on in the future; (2) within each of the areas suggested, to indicate three specific topics that need to be addressed more; and (3) within each topic, to illustrate analytical issues that warrant particular attention (see Web Appendix 5). Altogether, we received input from 43 social media marketing scholars who suggested 6 broad areas, 13 specific topics, and 82 focal issues for future research, which are presented in Table 5. Among the research issues proposed, finding appropriate metrics to measure performance in SMMSs seems to be an area to which top priority should be given. This is because performance is the ultimate outcome of these strategies, for which there is still little understanding due to the idiosyncratic nature of social media as a marketing tool (e.g., Beckers et al. 2017;Trainor et al. 2014). In particular, it is important to shed light on both short-term and long-term performance, as well as its effectiveness, efficiency, and adaptiveness aspects (e.g., Barger et al. 2016). Another key priority area stressed by experts in the field involves integrating to a greater extent various strategic issues regarding each of the marketing-mix elements in a social media context. This would help achieve better coordination between traditional and online marketing tools (e.g., Kolsarici and Vakratsas 2018;Kumar et al. 2017).
Respondents in our academic survey also stressed the evolutionary nature of knowledge with regard to each of the four SMMSs and proposed multiple issues for each of them. Particular attention should be paid to how inputs from customers and firms are interrelated in each of these strategies, taking into consideration the central role played by customer engagement behaviors and firm initiatives (e.g., Sheng 2019). Respondents also pinpointed the need for more emphasis on social CRM strategy (which is relatively under-researched), while there should also be a closer assessment of new developments in both marketing (e.g., concepts and tools) and social media (e.g., technologies and platforms) that can lead to the emergence of new types of SMMSs (e.g., Ahani et al. 2017;Choudhury and Harrigan 2014).
Respondents also noted that up to now the preparatory phase for designing SMMSs has been overlooked, and that therefore there is a need to shed more light on this because of its decisive role in achieving positive results. For example, issues relating to market/competitor analysis, macroenvironmental scanning, and target marketing should be carefully studied in conjunction with formulating sound SMMSs, to better exploit opportunities and neutralize threats in a social media context (e.g., De Vries et al. 2017). By contrast, our survey among scholars in the field stressed the crucial nature of issues relating to SMMS implementation and control, which are of equal, or even greater, importance than those of strategy formulation (e.g., Järvinen and Taiminen 2016). The academics also indicated that, by their very nature, social media transcend national boundaries, thus leaving plenty of room to investigate the international ramifications of SMMSs, using cross-cultural research (e.g., Johnston et al. 2018).

Theoretical implications
Given the limited research on SMMSs, this study has several important theoretical implications. First, we are taking a step in this new theoretical direction by providing a workable definition and conceptualization of SMMS that combines both social media and marketing strategy dimensions. The study complements and extends previous research (e.g., Harmeling et al. 2017;Singaraju et al. 2016) that emphasized the value of social media as resource integrator in exchanging customerowned resources, which can provide researchers with new angles to address the issue of integrating social media with marketing strategy. Such integrative efforts can have a meaningful long-term impact on building a new theory (or theories) of social media marketing. They also point to a deeper theoretical understanding of the roles played by resource identification, utilization, and reconfiguration in a SMMS context.
We have also extended the idea of "social interaction" and "social connectedness" in a social media context, which is critical because the power of a customer enabled by social media connections and interactions is of paramount • What is the dark side of the use of SM as a promotional tool?
Social content strategy Message strategy • What is the most effective content with regard to different devices, platforms, and industries?
• Which SM messages/content can help improve branding outcomes (e.g., brand loyalty)?
• Whether customer co-creation leads to less negative inferences and more valuable virality • What specific message strategies are needed to initiate C2C interactions to help the brand?
• Consumer reactions if learned that C2C social messages are incentivized by the firm?
• Ethical implications involved in viral marketing activity • How to measure social content marketing performance regarding customer outcomes?
• Coping with competitors' social content strategies • What are the implications of an effective social content strategy on the firm's resource allocation? Seeding strategy • Determinants of finding the most effective social influencers • Customer reactions to seeding programs and their interaction with marketing mix elements • What type of product/service and customer characteristics impact on seeding success?
• What price levels will make the influencer to engage in SM promotions and in which way?
Social monitoring strategy Listening • The role of different predictive analytics (e.g., machine learning) to get customer insights • What are the reasons for driving firms to start with customer engagement initiatives?
• What is the best way for firms to engage and how does this impact customer engagement?
• How do customer sentiments observed in different SM venues affect performance?
• Which social listening approach (i.e., manual, fully automated, hybrid) is the most appropriate? Responding • Does SM ease of use and pervasiveness elicit higher customer complaints?
• How SM responding promotes WOM and enhances market/financial performance?
• Using SM to stimulate positive publicity and minimize negative publicity • Ethical and legal considerations in firm responding • How do individual traits, cultural factors and brand perceptions affect responding strategies? importance in explaining the significance of SMMSs . More importantly, our study suggests that firms should take the initiative to motivate and engage customers, which will lead to wider and more extensive interactions. In particular, we show that a firm can leverage its social media usage through the use of different engagement initiatives to enforce customer interactivity and interconnectedness. Such enquiries can provide useful theoretical insights into the strategic marketing role played by social media in today's highly digitalized and globalized world. We are also furthering the customer engagement literature by proposing an SMMS developmental process. As firmcustomer relationships evolve in a social media era, it is critical to identify those factors that have an impact on customer engagement. Although prior studies (e.g., Harmeling et al. 2017;Pansari and Kumar 2017) have demonstrated the engagement value contributed by customers and the need for engagement initiatives taken by firms, we are extending this idea to provide a more holistic view by highlighting the role of insights from both firms and customers to better understand the dynamics of SMMS formulation. We also suggest certain theories to specifically explain the role played by each of the components of the process in developing sound SMMSs. We capture the unique characteristics of social media by suggesting that these networks and interactions are tightly interrelated with the outcome of SMMS, which is customer engagement. Our proposed SMMS developmental process may therefore provide critical input for new studies focusing on customer engagement research.
Finally, we build on various criteria to distinguish among four SMMSs, each representing a different level of strategic maturity. We show that a SMMS is not homogeneous, but needs to be understood in a wider, more nuanced way, as having different strategies relying on different goals and deriving insights from firms and their customers, ultimately leading to different customer engagement levels. In this regard, the identification of the key SMMSs stemming from our analysis can serve as the basis for developing specific marketing strategy constructs and scales within a social media context. We also indicate that different SMMSs can be implemented and yield superior competitive advantage only when the firm is in a position to devote to it the right amount and type of resources and capabilities (e.g., Gao et al. 2018;Kumar and Pansari 2016). • Customer engagement effects on product perceptions (e.g., quality, satisfaction) • How do specific types of digital engagement practices contribute differently to brand equity?
• How do differences in modality, self-disclosure, and privacy translate to digital engagement?
• What are the most effective strategies to gain deeper and long-lasting customer engagement?
CRM capabilities • Capabilities needed to generate/integrate/reconfigure SM resources to achieve advantages • Determinants of SM capabilities (e.g., data analysis, data synthesis, data interpretation) • How can SM interactions be transformed into valuable marketing resources?
• How can SM data/tools be leveraged to generate customer insights and help in new product development? • How do social CRM strategies differ in inexperienced and experienced firms using SM?
• How do different strategic decision-making styles influence social CRM strategy outcomes?
• What resources/capabilities are needed to implement an effective social CRM strategy?

Miscellaneous
Relationship marketing aspects • How does trust and commitment in a SM context facilitate marketing strategies?
• What kind of relational resources can be strategically used in SM?
• How is value co-created between sellers and buyers in a SM context?
• How does the intensity of SM interaction improve the quality of customer relationships?
Service marketing aspects • How is service both positioned and delivered in SM?
• How is customer service experience on SM different from the traditional service provider?
• How do service providers cope with multi-channel environments in SM?
International marketing aspects

Managerial implications
Our study also has serious implications for managers. First, our analysis revealed that the ever-changing digital landscape on a global scale calls for a reassessment of the ways to strategically manage brands and customers in a social media context. This requires companies to understand the different goals for using social media and to develop their strategies accordingly. As a starting point, firms could explore customer motivations for using social media and effectively deploy the necessary resources to accommodate these motivations. They should also think carefully about how to engage customers when implementing their marketing strategies, because social media become resource integrators only when customers interact with and provide information on them (Singaraju et al. 2016). Managers need to set objectives at the outset to guide the effective development, implementation, and control of SMMSs. Our study suggests four key SMMSs achieving different business goals. For example, the goal of social commerce strategy is to attract customers with transactional interests, that of social content strategy and social monitoring strategy is to deliver valuable content and service to customers, and that of social CRM strategy is to build mutually beneficial customer relationships by integrating social media data with current organizational processes. Unfortunately, many companies, especially smaller ones, tend to create their social media presence for a single purpose only: to disseminate massive commercial information on their social media web pages in the hope of attracting customers, even though these customers may find commercially intensive content annoying.
This study also suggests that social media investments should focus on the integration of social media platforms with internal company systems to build special social media capabilities (i.e., creating, combining, and reacting to information obtained from customer interactions on social media). Such capabilities are vital in developing a sustainable competitive advantage, superior market and financial performance. However, to achieve this, firms must have the right organizational structural and cultural transformation, as well as substantial management commitment and continuous investment.
Lastly, social media have become powerful tools for CRM, helping to transform it from traditional one-way interaction to collaborative interaction. This implies that customer engagement means not only encouraging customer engagement on social media, but also proactively learning from and collaborating with customers. As Pansari and Kumar et al. (2017) indicate, customer engagement can contribute both directly (e.g., purchase) and indirectly (e.g., customer knowledge value) to the firm. Therefore, interacting with customers via social media provides tremendous opportunities for firms to learn more about their customers and opens up new possibilities for product/service co-creation.

Conclusions
The exploding use of social media in the past decade has underscored the need for guidance on how to build SMMSs that foster relationships with customers, advance customer engagement, and increase marketing performance. However, a comprehensive definition, conceptualization, and framework to guide the analysis and development of SMMSs are lacking. This can be attributed to the recent introduction of social media as a strategic marketing tool, while both academics and practitioners still lack the necessary knowledge on how to convert social media data into actionable strategic marketing tools . This insufficiency also stems from the fact that the adoption of more advanced SMMSs requires the possession of specific organizational capabilities that can be used to leverage social media, with the support of a culture that encourages breaking free from obsolete mindsets, emphasizing employee skills with intelligence in data and customer analytical insights, and operational excellence in organizational structure and business processes (Malthouse et al. 2013).
Our study takes the first step toward addressing this issue and provides useful guidelines for leveraging social media use in strategic marketing. In particular, we provide a systematic consolidation and extension of the extant pertinent SMMS literature to offer a robust definition, conceptualization, taxonomy, and validation of SMMSs. Specifically, we have amply demonstrated that the mere use of social media alone does not generate customer value, which instead is attained through the generation of connections and interactions between the firm and its customers, as well as among customers themselves. These generated social networks and influences can subsequently be used strategically for resource transformation and exchanges between the interacting parties. Our conceptualization of the SMMS developmental process also suggests that firms first need to recognize customers' motivations to engage in brand-related social media activities and encourage their voluntary contributions.
Although the four SMMSs identified in our study (i.e., social commerce strategy, social content strategy, social monitoring strategy, and social CRM strategy) denote progressing levels of strategic maturity, their adoption does not follow a sequential pattern. As our validation procedures revealed, this will be determined by the firm's strategic objectives, resources, and capabilities. Moreover, the success of the various SMMSs will depend on the firm's ability to identify and leverage customer-owned resources, as in the case of transforming customers from passive receivers of the firm's social media offerings to active value contributors. It will also depend on the firm's willingness to allocate resources in order to foster collaborative conversations, develop appropriate responses, and enhance customer relationships. These will all ultimately help to build a sustainable competitive advantage and enhance business performance. Social commerce strategy □ L'Oréal, the French cosmetics company, has been fore-fronting to incorporate social media technologies into their business. L'Oréal launched the social commerce platforms on Facebook, which allows its potential customers to make a purchase via social media. Meanwhile, it provides direct on-demand interactions through chats with customers, which boost the average inquiry-to-sale conversion rate to 22% in 5 months. Source: Acommerce (2019) □ ASOS, the UK-based fashion retailer without any physical storefronts. As reported, ASOS made a 28% increase in annual profits from 2017 to 2018 of online sales due to the proper leverage of social media as the promotional tool. Moreover, the company has humanized social media interactions with their fans by providing personal touches and down-to-earth conversations in their Facebook and Twitter feeds. Consequently, the appropriate social commerce strategy has made ASOS fast-moving and differentiated in the fashion business. Source: Robert (2018) Social content strategy □ Nike, the globally well-known sportswear giant, has been successful in the social content strategy. Through a mix of effective content from celebrity-endorsed narrative to emotional storytelling, Nike has moved beyond the domain of selling products to branding themselves as a lifestyle. Now, with 77 million followers, Nike is the second most followed brand on Instagram, while its Facebook account is among the top ten most followed. Source: Ravi (2018) □ In the case of Dove's "Real Beauty Sketches" campaign in 2013, the short film has become the most-watched online branded video with over 163 million views globally. The pace of content sharing in that campaign was unprecedented due to the compelling and emotional message, which has resonated with a massive audience. The success of the campaign led to a surge of customer engagement and over a million of 'likes' on the Dove Facebook page. Source: Stampler (2013) Social monitoring strategy □ In 2014, Hertz Rent-a-Car announced their social media strategy shift from marketing-oriented view to a customer-oriented view. Thus, Hertz built a 24/7 global social customer care system aiming to improve efficiency and quicker response through social media monitoring. As reported, customer loyalty has been notably increased due to the immediate responding via social media. Source: Waldo (2014) □ An example of leveraging social monitoring can be well illustrated by Barclays bank's new launch of mobile payment app called PingIt. Instead of a traditional product launch approach, Barclay used real-time social media data analysis to listen to customer feedbacks and complaints concerning the app. Within a short period, Barclays made significant changes to the app and successfully turned the customers' negative mentions into valuable market knowledge. Source: Griffith (2016) Social CRM strategy □ In coping with increasingly fierce competition and declined customer value in the Chinese market, the US cosmetics brand Max Factor launched a new social CRM system in 2016. The system enabled a new loyalty program as a result of the connection of customers' social behavior data and detailed offline data. In addition, it also empowered real-time, automated, and customized communication system. The company gained more in-depth customer insights and increased average customer purchase value in just four months. Source: Wang (2017) □ Fiat Brazil's car crowdsourcing project is an excellent example to enlighten the importance of customer engagement through co-creation in social CRM strategy. Fiat has recognized customers as a new source of innovation and invited them to share their novel ideas in creating a concept car. In twelve months, Fiat's online platform received suggestions from over 17,000 people across 160 different countries, which results in the world's first crowdsourced car. Source: Saldanha et al. (2014) Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. 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