Introduction

At the 2022 ISTR 15th International Conference “Navigating in Turbulent Times: Perspectives and Contributions from the Third Sector” in Montreal, Canada, founding Voluntas editor Helmut Anheier summarized a continuous key challenge of third sector studies: conducting cross-national, comparative research. This very topic started on the pages of Voluntas from the journal’s inception in 1990. We intend to use this virtual issue of Voluntas to explore the comparative approaches to third sector research that have developed in the journal. Voluntas was and remains a major outlet for considering civil society and the third sector in comparative perspective. However, just as recent as 2021, former Voluntas editors Ruth Simsa and Taco Brandsen (2021) noted that cross-national research in Voluntas was still “rare” (p. 2), calling on the field to engage in more comparative work.

This virtual issue introduction has two main objectives. First, we conduct an outline of comparative discussions as they unfolded in Voluntas, complementing Anheier’s recent editorial about the progress of comparative research (Part 1). Second, in the spirit of encouraging further comparative research in the field, we highlight exemplar comparative articles in Voluntas which make theoretical and methodological contributions, and which employ a range of qualitative and quantitative comparative approaches (Part 2).

PART 1: Comparative Research in Voluntas

Comparative analysis sets out to examine similarity and variance among what is being analyzed. We focus here on comparative research limited mostly to cross-national comparisons, what is generally central to the discussion of comparative approach in the field (see Anheier et al., 2020). Since Voluntas’ first issue in 1990, founding editors Anheier and Knapp (1990) wrote of a “growing international interest” (italics in the original) in the field of civil society and third sector studies. Voluntas was created, in part, to complement Nonprofit Voluntary Sector Quarterly and respond to a “need for an international dimension in the study of the voluntary sector” (p. 1). Interestingly, they noted that countries outside of North America and Europe were “isolated from the study of the sector” (p. 2). This concern and shortcoming have been mentioned time and time again in Voluntas over the years. Anheier and Knapp (1990) outlined what they were looking for in terms of submissions and it remains consistent; cross-national questions were important then and remain so today. They called comparative research “a central aspect” of the journal, and stated: “ultimate goal of a journal such as Voluntas must be to encourage the cross-national and cross-disciplinary fertilization of theoretical developments and empirical insights” (Anheier & Knapp, 1990, p. 11).

Definitional and Classification Debates

In the first 7 years of Voluntas, 10% of the articles covered definition and classification issues (see 10-year review by Hodgkinson & Painter, 2003). In 1992, Salamon and Anheier (1992a) introduced their structural–operational definition of nonprofit organizations which they claimed allowed for comparative, cross-national research. They argued that research was lacking on the voluntary sector because of the weakness in the concepts which defined it. Under the structural–operational definition, nonprofits are: (1) formal and have structure; (2) private, as they are not part of government or ruled by it; (3) uphold the nondistribution constraint as they reinvest their profits into the mission of the organization without sharing it with owners or investors; (4) independent over their own decisions and procedures; and (5) to some degree, their work relies on nonpaid volunteers (Salamon & Anheier, 1992a). This definition outperformed others (e.g., legal, economic/financial, and functional definitions) and they applied it to the UK, USA, and Brazil country cases.

The next two Voluntas articles by Salamon and Anheier (1992b, 1993) took the focus from definition to classification. They set forth a classification system “that can be used to differentiate systematically the types of nonprofit organizations that exist at the global level” (1992b, p. 267). They outlined different various classification systems and then proposed an alternative: International Classification of Nonprofit Organizations (ICNPO). Presenting the ICNPO, they touted that specifically “[c]lassification is the crucial prerequisite for scientific progress in any field of study” (p. 288). Informed by their work on the Johns Hopkins Comparative Nonprofit Sector Project (CNP), a major comparative study at the time, Salamon and Anheier (1993) continued to argue that the structural–operational definition was superior and posited the best classification scheme as ICNPO. The article moved the conversation further to consider cross-national data collection by using existing data sources and national income accountingFootnote 1 (Salamon & Anheier, 1993, p. 551).

During this time, there were also discussions—in policy circles and in Voluntas—about how nonprofits were being included in the United Nations System of National Accounts (SNA), which countries use to report their economic activity (e.g., Anheier et al., 1994). A challenge to SNA was the limited definition of “nonprofit organizations” which skewed the economic activity they contribute. Called “non-market organizations serving households,” this definition disregarded the various types of nonprofits (e.g., those collecting fees) which were put into the other sectors (government, corporate, and households, e.g., those nonprofit collecting fees would be captured in the corporate, not the nonprofit, sector).

These initial articles rested on the proposition by Salamon and Anheier that definition and classification are required steps for both theoretical development and empirical analysis in the field. Recognizing this foundational work, at-the-time new Voluntas editor, Jeremy Kendall in 1998 wrote that the journal: “made major inroads into the task of systematic and scientific comparison between countries, and the interpretation of national evidence and experience, within the internationally developed and understood theoretical frameworks that must form the core of any attempt to build a new international research community” (Kendall, 1998, p. 3).

Social Origins Theory and Responses

The previous articles by Salamon and Anheier on definition, classification, and measurement (via the CNP and SNA) fed into their seminal article “Social Origins of Civil Society: Explaining the Nonprofit Sector Cross-Nationally” published in Voluntas in 1998. In the article, Salamon and Anheier (1998a) assessed a range of theories that sought to explain variation of the nonprofit sector (e.g., size, the composition, financing) across country contexts. These theories were (1) government failure/market failure theory; (2) supply-side theory; (3) trust theories; (4) welfare state theory; and (5) interdependence theory.

They argued that each had substantial weakness and proposed the “social origins” theory to better account for social, political, and economic relationships. This theory allowed them to argue four paths to nonprofit sector development: the liberal, the social democratic, the corporatist, and the statist (this was later extended to include a fifth, the traditional path, see Salamon et al., 2017; Salamon et al., 2023). Salamon and Anheier (1998a) provided hypotheses to test all of the theories with data from CNP, focusing on nonprofit sector size and nonprofit finance. Despite the data limitations and challenges with variable operationalization, in 1998 they argued that social origins theory provided a way to explain the development of the sector, capturing cross-national variations.

Drawing on institutional choice theories (namely, Barrington Moore Jr.’s "social origins" of fascism and democracy [1966] and Gøsta Esping-Andersen’s origins of the modern welfare state [1990]), social origin theory was grounded on the idea that complex phenomena (e.g., democracy, the welfare state) “cannot be easily understood as the product of the unilinear extension of a single factor, such as industrialization, diversity, or education. Rather, much more complex interrelationships among social classes and social institutions are involved” (p. 226). This perspective drew attention to power and its balance across the social classes. Salamon and Anheier (1998a) argued that this reasoning can be useful in questions about the nonprofit sector. They contended that the theory can complement the economic theories that had attempted to explain the sector and effectively integrate a comparative historical approach. The theory proposed “a finite set of more or less distinct ‘models’ or ‘regimes’ that can be traced to an identifiable, and predictable, set of social circumstances—precisely what our analysis of alternative theories suggests is needed” (Salamon & Anheier, 1998a, p. 241).

In the same Voluntas issue (Volume 9, Issue 3), economists Richard Steinberg and Dennis Young (1998) responded. They acknowledged from the start that CNP: “is the most important descriptive empirical research on the nonprofit sector of the last decade. For the first time in the history of this field of study we are able to measure and document the size and scope of the third sector using consistent definitions across multiple nations” (Steinberg & Young, 1998, p. 249). However, they had concerns, specifically about the data. They cautioned about the ICNPO and their apprehension about its criteria that eliminate entities that might be more informal, more embedded in markets or are religious organizations that provide services and play important roles in civil society. Among several criticisms, indeed, they wanted to see more attention to religion, in particular, religion’s role in entrepreneurialism and its other influences.

Renowned methodologist Charles Ragin also provided his feedback on the social origins theory. In the same Voluntas issue, he took the stance: “cross-national research on the nonprofit sector needs to move in a more qualitative and historical direction” (Ragin, 1998, p. 262). He was hesitant about the ability of a large N study of a phenomenon like the nonprofit sector. He argued for more focus on comparative and historical research (Ragin, 1998), due to the sector’s diversity and heterogeneity. He explains: “Thus, the historical development of nonprofit organizations is likely to be country-specific, and within countries, subsector-specific. In the end, comparative analysis should be grounded in in-depth knowledge of the historical development of specific subsectors across cases” (Ragin, 1998, p. 262).

Still in the same Voluntas issue, Salamon and Anheier (1998b) were able to reply to Steinberg and Young (more economic) and Ragin’s (more comparative historical) reactions. Salamon and Anheier (1998b) organized their reply across three overarching themes: the definition of the sector, measurement challenges, and the testing of theory. First, they stood by, given their process of elimination of the alternatives, the structural–operational definition of nonprofit organizations. They reiterated the challenges of available data and the limited means in which they have to use better indicators, requiring the need to be satisfied with “second-best solutions” (p. 278). This led to concerns beyond the indicators to include questions about the ways the theories proposed were tested. Steinberg and Young and Ragin were uneasy about the use of bivariate tests and the assumption of linear relationships, but Salamon and Anheier (1998b) accepted what was admittedly a “minimalist route” (p. 279).

Defining the Sector and its Measurement Re-emerges

In 2016, after some time of continued work on the social origins theory (e.g., Salamon et al., 2004), Salamon returned to Voluntas, with co-author Wojciech Sokolowski, to revisit the issues around defining the sector. In the article “Beyond Nonprofits: Re-conceptualizing the Third Sector,” Salamon and Sokolowski (2016) observed the ongoing work of European colleagues in conceptualizing the sector and for the first time recognized a broader concept of the “third sector.” One dimension that was in tension with the nonprofit sector is that of the social economy, familiar in several European countries, and particularly in Southern Europe (Italy and Spain) and Latin America. Thus, they transitioned from seeking a definition of the nonprofit sector to one of conceptualizing a “common core” of the third sector (p. 1523). They identified a broader third sector as: “(i) NPOs, (ii) mutuals and cooperatives, (iii) social enterprises, and (iv) human actions such as volunteering and participation in demonstrations and social movements that are undertaken without pay” (p. 1530) and established what they termed as the third sector/social economy (TSE) sector. This new attempt to define (or conceptualize) the sector opened room for cooperatives, mutual, and social enterprises.

As was the model previously in Voluntas, in the same issue (Volume 27, Issue 4), several authors in the field were invited to respond. Defourny et al. (2016) provided their individual impressions, in a collective piece, of the new “conceptualization” which moved the boundaries of the third sector. Defourny and Nyssens outlined two approaches: the social economy approach focused on democratic processes and the nonprofit approach which centered on the nondistribution constraint. They criticized that democratic governance was still not an important part of new conceptualization by Salamon and Sokolowski. Grønbjerg drew attention to the limitations around boundaries between the nonprofit sector and the public sector and the implications of cross-sector collaborations/relations. Mejis noted the need to consider the new conceptualization regarding clients who are served and members who engage, he also suggested further attention to relationships with the private/business sector. Yamauchi applied the new conceptualization to the Japanese context and posed questions about instances when both nonprofit and for-profit behavior is present in a single organization.

While there was a several year break from this debate in Voluntas after 2016,Footnote 2 when Voluntas put the call out for what became a two-volume series on methodology (see Kim & Raggo, 2022, 2023), not surprisingly, Salamon responded with a new contribution. Sadly, Salamon passed away during the article’s revision process. Longtime collaborators, Megan Haddock and Stefan Toepler were asked whether they could provide revisions and, to the best of their abilities, reflect the spirit of Salamon’s ideas and intentions (Salamon et al., 2023). This 2023 paper takes most of the work outlined above and in greater detail presents a narrative and timeline of the quest to build a comparatively focused field orientation: starting with the John Hopkins Comparative Nonprofit Sector Project, then engaging with the UN in the SNA process, and then in 2016 broadening of the definition of the sector itself. The call left by Salamon et al. (2023) focuses on the need to improve the SNA and work with national statistics offices. However beyond that, we have a responsibility as scholars, they concluded: “The near-term future of solid, cross-national empirical research and empirically based theory-building in the third sector field may well depend, however, on the sustained engagement of the research community” (Salamon et al., 2023, p. 123).

Complementary Discussions about Comparison in Voluntas

During the definitional and classification discussions and the emergence of social origin theory, economist Estelle James joined as a keynote speaker at the second International Society for Third-Sector Research’s conference in Mexico City, July 1996 with a talk titled, “Whither the Third Sector? Today and Tomorrow.” A version of her speech was published in Voluntas in 1997 (James, 1997). James was an economist working on international comparisons of public–private sector interactions in the provision of education (1983, 1987). Her 1997 published reflections took stock of the questions that were asked back in the 1980s, namely why did the third sector experience growth, how was the sector funded, and how did nonprofits behave (in comparison to the government and market sectors). Admittedly, most of this research was conducted in the contexts of USA and UK. She recognized that in the 1990s, new topics were complementing the old, including nonprofits outside of service delivery (working in advocacy, for example) and capturing the trends of decentralization and participation. However, she wrote: “I am struck by the absence of comparative research in the field” (p. 5). She charged the field then in 1997 to continue with the traditional questions and current trends on the sector using comparative perspectives as a first step. She highlighted further topics that pose interesting research puzzles, such as the role of nonprofits in development and the ideas of the third sector and civil society as it related to nonprofits.

Directly responding to her, Alan Fowler, as a recognized academic with experience in practice, published in 1998 in Voluntas the article, “Whither the Third Sector? A Response to Estelle James.” He weaved into the comparative research conversations an important underlying theme: There seemed to at times be duplicate paths: one rooted in an economic perspective with theories derived mostly in Western contexts and another that explored conditional factors, behaviors and relationships of nonprofits working in development (Fowler, 1998). This development perspective had mostly contributed “gray” literature, not often drawing on scholarly theory nor with the intention to contribute to scholarly knowledge production and it was often country-specific. However, as Fowler noted, this knowledge production explores many of the questions James had proposed. Fowler suggested too that development studies would fare well by pulling nonprofit theories into their comparative and international research (see also Lewis, 1998; and Lewis’ (2015) later piece in Voluntas on the “parallel universes” of nonprofit studies and development studies).

The 2000s: What About Global Civil Society?

In 2002, Fowler returned to the conversation in Voluntas, recognizing the continued interest in “examining, describing, and explaining” civil society (Fowler, 2002, p. 287). However, he remained cautious given what he saw as the “economic bias” in the field (p. 289). He lamented the “moral and socioeconomic” positioning in lieu of the politicalness of civil society (see also Taylor [2002] and Munck [2006] about these topics in the 2000s in Voluntas). However, he recognized the benefit from the CNP and other projects that broadened the scope of empirical work outside of the global North. Whether this brought more interest and more study versus distorted the concept outside of the global North was still debated in the 2000s.

A handful of years later, Anheier (2007) also returned to the pages of Voluntas with “Reflections on the Concept and Measurement of Global Civil Society.” He again focused on the conceptual and methodological concerns related to comparative research. At this point in Voluntas (and beyond) he identified the debate as “overly focused on the issue of definitions relative to empirical research findings” (p. 3). He called on needed assessment about the empirical focus and how it had advanced (or not) research on global civil society. He recognized the tension in the literature with global civil society attributed to a Western, modernization project and the neglect of its normative status. Anheier drew attention to what is clear for many in the field: what whatever definition or understanding that is used for global civil society is not free of bias. He points to a “basic methodological principal: definitions are neither true nor false by themselves. They are conventions, based on conceptual plausibility and coherence, and the promise of reliable and valid observation” (p. 4). Anheier claimed that it was standard social science practice, that is, using empirics to bring greater understanding to a little understood phenomenon. In the end, he pinpointed some of the challenges in the field at this point in the late 2000s asking, is global civil society to be thought of as a “normative ideal” or as an occurrence that can be empirically observed?

Comparative Research on Civil Society and the Third Sector Today

We have seen in Voluntas a slight uptick of content around comparative approaches. Most recent is the already mentioned editorial by Anheier just published. In addition, von Schnurbein et al. (2018) review on nonprofit comparative research published in Voluntas explores the main drivers in the nonprofit comparative research agenda. They argue that the benefits of conducting a comparative study include conceptual refinement and insight into the specific and general forces underlying a phenomenon (von Schnurbein et al., 2018, p. 437). They find some research topics are consistent, that researchers are interested in government–nonprofit relations and the role of nonprofits in different contexts. However, they lament that despite the objective of comparative research to build theory, they found this to be minimal in the articles reviewed.

An additional contribution in Voluntas is Wiepking's (2021) article titled “The Global Study of Philanthropy Behavior” which also warrants mention. Wiepking’s text could exchange the topic of philanthropy to many of the relevant topics in the field—volunteering, governance, social enterprise, etc.—as she explores questions around studying the macro-level dimensions. As a field that has done better at asking micro- and meso-level questions, she argues (following Barman, 2017) that comparison is a central part of this, she says “We need to better understand, measure and explain the variation in philanthropic behavior in all its forms across geographical units, and only then, we can contribute to evidence-based interventions to stimulate philanthropic behavior leading to improved societal outcomes” (p. 197). She proposes both qualitative comparative study (for theory building) and then quantitative comparative study (for operational, measurement and theory testing).

PART 2: Empirical Studies Using Comparative Approaches in Voluntas

Here we select ten exemplar empirical articles published in Voluntas that contribute to comparative third sector research by using qualitative, quantitative and/or mixed-methods comparative approaches. For this virtual issue, we focus on comparison of two or more macro-social units, which can be countries or regions (including comparison at the subnational levels). We organize the articles thematically below (volunteering; philanthropy and charitable giving; advocacy and policy; cross-nationally comparing organizations; and co-production) and summarize them in Table 1.

Table 1 Ten exemplar Voluntas articles of comparative third sector research
Full size table

Volunteering

A sizable amount of quantitative comparative research in Voluntas focuses on volunteering, we suspect largely due to the availability of data. Such studies compare different aspects of voluntary participation, e.g., formal and informal volunteering, volunteering in public and private organizations, or organized and spontaneous volunteering. Some studies also examine specific age groups, like youth or senior citizens, while others consider gender as an important demographic factor.

Enjolras (2021) aims to explain the variations in formal volunteering across 23 European countries based on the capability approach. Utilizing data from the 2015 European Union Survey on Income and Living Conditions (EU-SILC), the two-step multilevel model effectively examines individual- and country-level factors affecting volunteer rates. The results reveal a positive association between human, economic, and social capital and volunteerism at the individual level. At the contextual level, the study stresses that the level of inequality and social trust influence individual capabilities to volunteer. The study reconciles the capability approach with the social origins theory by suggesting that equality and social trust could be crucial channels through which historically established institutional characteristics influence individual capabilities to engage in volunteering.

There have been efforts to gain a better understanding of volunteering in countries outside the Western sphere. Wang and Han (2023) make an important contribution by examining volunteering in Asian contexts from a gender perspective. They use social role theory and social capital theory to investigate how gender, social role, and social capital influence the likelihood of volunteering. The study uses data from the 2012 East Asia Social Survey to compare volunteerism in China, Japan, South Korea, and Taiwan. The regression results support social role theory and the influence of social capital indicators. However, the findings also suggest that social roles may not be the primary factor in explaining gender disparities in volunteering. Instead, the study reveals that social capital, particularly participation in secular groups, can moderate gender differences in volunteering.

Another exemplar study about volunteering in non-Western contexts is conducted by Compion et al. (2022), who examine event-based episodic volunteering across three African countries: Ghana, South Africa, and Tanzania. The authors analyze how distinct motivations—altruistic, utilitarian, and social—predict the likelihood of an individual being a novice, occasional, and regular episodic volunteer. The results indicate that newcomers are primarily motivated by the social aspect, while regular volunteers exhibit stronger altruistic motivations. The study contributes by shedding light on event-based episodic volunteering in African nations. Given the prevalence of informal, individual volunteering over membership-based volunteering in these countries, the study’s focus on episodic volunteering holds relevance.

Philanthropy and Charitable Giving

We find quantitative comparative research has predominantly focused on philanthropy and charitable giving. Einolf's (2017) study reveals that theories explaining charitable giving in Western countries may not be effective in explaining the variations observed in low-income non-Western samples. We chose this article as an example not primarily based on its quantitative methodological approach, as its multivariate regression model may have a multicollinearity issue and is limited to a small sample size due to the use of country-level average data, as also noted by the author. However, the paper’s classification into Western versus non-Western and further subcategorization into low-income and middle-income non-Western countries, provide valuable insights into the importance of theory testing across diverse contexts. The key takeaway from this paper is that economic factors are the primary driver of differences in charitable giving across nations. In this sense, the paper raises an intriguing question about charitable giving in low-income countries: Are the factors that predict variation in low-income countries simply different from those in other countries, or do giving patterns become predictable only when economic development reaches a certain level?

The study by Katz-Gerro et al. (2015) presents an example of quantitative comparative research in philanthropy, specific to environmental causes, an area that has not been extensively studied in the literature. Katz-Gerro et al. (2015) investigate the effects of globalization compared to those of local contexts, adding to the debate on convergence versus divergence under global ideas and norms. The study aims to determine whether environmental behaviors among university students in five selected countries—Canada, Germany, the USA (Western countries), Israel (Middle East), and South Korea (Asia)—exhibit similar patterns and can be explained by individual-level predictors. The results demonstrate notable variations in environmental behavior among the countries, even after controlling for individual-level predictors. This challenges the notion that countries, and especially young people from the studied regions, would converge in terms of environmental philanthropy under global norms. Moreover, these findings suggest that country context still plays a significant impact on environmental activities and philanthropic behaviors.

Advocacy and Policy

Advocacy is one of the essential functions of nonprofits. By engaging in policy formulation and encouraging constituency empowerment, nonprofits represent the interests of society and facilitate policy change. Yanagi et al. (2021) enhance the understanding of nonprofit advocacy by introducing its association with nonprofit service delivery. Specifically, the study differentiates between the impact of service provision and government funding on advocacy. The authors analyze survey data collected from the Japan Interest Group Study, which includes data from Japan, South Korea, the Philippines, and the USA. The results demonstrate a consistent positive influence of service provision on advocacy across all four countries. Yet, the impact of government funding varies depending on the country and region. This suggests that an organization's identity as a service provider is a key motivation for nonprofits to engage in advocacy, and establishing networks with government explains an underlying mechanism. The study suggests that previous research may have overestimated the beneficial effects of government funding on nonprofit advocacy, indicating a need for further examination.

A mixed methods study selected among the articles also explores policy questions. Martínez-Carmona's (2022) study aims to understand the causal impact of social movements on the formulation of abortion and equal marriage policies in Mexico. Here, the author's analysis is a comparative examination of 27 policies enacted across 12 different Mexican states over the period from 2007 to 2017. These states were selected to represent a wide spectrum of policy orientations. The author employs the qualitative comparative analysis, combining elements of qualitative research, particularly case-oriented inquiry, with quantitative research components, including variables definition to suggest causal relationships. The analysis underscores the key role of social movements in propelling more progressive policies concerning abortion and equal marriage. However, Martínez-Carmona highlights that the mere presence of social movements is insufficient; other factors, such as the existence of favorable legal precedents, must also be in place to facilitate policy change.

Cross-Nationally Comparing Organizations

Voluntas’ scope from the beginning has sought studies comparing nonprofit and third sector organizations. In line with this, McMullin and Skelcher (2018) explore nonprofit organizations as hybrid organizations, that is, entities that embody characteristics from various sectors of society. Drawing upon the literature of institutional logics in organizational studies, they ask: "How do distinct combinations of institutional logics in England and France influence the manifestation of hybridity within non-profit organizations?." What is exceptional about McMullin and Skelcher’s qualitative comparative research is that it establishes a clear rationale for cross-national comparison. The selection of countries for comparison centers on England and France. This selection, underpinned by both the most different case sampling and theoretical sampling methodologies, is rooted in the fact that, while both countries boast structured nonprofit sectors, their welfare regimes, and broader institutional and governance contexts, encompassing divergent institutional logics, exhibit striking differences. Additionally, the authors establish a discussion with the social origins theory, specifically regarding the evolution of the third sector and its relationship with the welfare state. The authors delve into how the state, community, and market institutional logics influence the hybridity exhibited by the organizations within each context.

Also addressing nonprofit organizations, Gidron et al. (1999) employ a blend of organizational and social movement theories to assess the characteristics and operational dynamics of nongovernmental organizations specializing in the prevention and resolution of humanitarian conflicts, often referred to as peace and conflict resolution organizations. To accomplish their research objectives, the authors selected three distinct regions mired in violent conflict: Northern Ireland, South Africa, and Israel/Palestine. It is worth noting that despite the considerable differences among these conflicts, a common thread emerges. All three underwent significant political upheavals in the 1990s, signaling potential resolutions to their respective conflicts (notably, the article itself was published during the 1990s). Furthermore, the period leading up to these political shifts witnessed a marked expansion of the third sector's engagement in these conflict zones. Building upon these comprehensive analyses and detailed case descriptions, the authors uncovered overarching characteristics shared by all these organizations related to professionalization, relationships with external funding sources, and the strategic diversity in organizations’ approaches. Nonetheless, the authors emphasize the significant influence of contextual factors on these organizations' culture and overall sustainability.

Co-production

Co-production has found its place on the Voluntas’ pages by proposing more collective processes of producing goods, services, and policies that rely on the participation of a diverse sets of actors and organizations. Surva (2022) studies co-production and its rapid digitization in response to the COVID-19 pandemic in 2020. The author considers services in restorative justice, which confront conflict or crime by deliberately engaging all affected parties, including “the victim, the offender, and the community—in order to repair harm” (pp. 693–694), spanning four European countries: Estonia, Finland, Ireland, and Portugal. The author uses the theoretical framework of the normalization process. The article seeks to unravel the immediate consequences of digitalization on the collaborative production of restorative services, and it investigates how digitally mediated practices underwent normalization while preserving the fundamentally co-productive essence of restorative justice. The selection of the four countries was predicated on two key variables. First, Surva's considers the degree of establishment of restorative justice services within each country. Second, the author assessed the level of digital proficiency these nations exhibited according to international benchmarks.

Summary

The selected articles address a variety of topics in our field, at times studying different units of analysis and employing diverse research approaches. The conversations about comparative research in Voluntas over the years intended to clarify issues of definition, classification and measurement in order to both build and test theory, comparatively. Based on the articles we found particularly effective, the quantitative comparative research articles often sought to test theories across diverse contexts and several emphasize the significance of cross-country comparison in developing theory as well. For example, quantitative studies by Yanagi et al. (2021) and Enjolras (2021) focused on theory testing and development by introducing new explanatory variables to existing models or by proposing a new approach.

For the selected qualitative studies, there was evidence of in-depth analysis of various dimensions and mechanisms such as structural attributes, agency, behavioral patterns, as well as the external environment in which the third sector operates. These articles not only facilitate the development of insights pertaining to the specific cases under examination but also take an active role in advancing and refining the theoretical frameworks they employ. For example, McMullin and Skelcher (2018) and Gidron et al. (1999) develop the domain of organizational theory by, deepening the understanding of hybrid organizations, and offering a comprehensive characterization of peace and conflict resolution organizations, respectively. Additionally, there are articles that adeptly employ established theoretical frameworks to yield insights in alternative dimensions, as Surva's (2022) examination of the digitization of restorative practices during the COVID-19 pandemic, where the focus is on enhancing our understanding (and test theory) in a specific context.

As evidenced by the selected articles, there are multiple and varied methodological approaches for comparative research on civil society and the third sector. Even in the debates in the late 1990s, Salamon and Anheier (1998b) called for methodological diversity—something that is relevant still on the pages of Voluntas (e.g., Dodge et al., 2022; Searing & Berkovich, 2022). Innovative methods and data are being used. For example, the primary data source for the selected quantitative studies is cross-sectional survey data. In certain cases, the research team conducted the surveys themselves (Compion et al., 2022; Katz-Gerro et al., 2015; Yanagi et al., 2021). In the qualitative articles, the predominant methodology employed is the case study, facilitating extensive data concerning the subjects under investigation. In this context, key data were from interviews, documents, and observations.

Comparative studies can benefit significantly from, while considering the limitations, the increasing availability of data sources, the growing adoption of computational methods, and the openness in the field for critical perspectives. Indeed, as suggested by Searing and Berkovich (2022), the use of diverse data sources can lead to an expansion of research methodologies. For example, researchers could leverage structural topic models with social media messages (Wu, 2023) or consider the spatial dimension of organizations (Dipendra & Lorsuwannarat, 2022; MacIndoe & Oakley, 2023) in comparative contexts. Incorporating social media as a data source has the potential to provide comprehensive global insights and overcome the limitations associated with relying solely on reporting-centric data (Bloodgood et al., 2023; Searing & Berkovich, 2022). Importantly, scholarship using critical perspectives is already welcomed in Voluntas and growing more widely in the field (Eikenberry et al., 2023) and it could have a greater presence in and inform more comparative research.

Additionally, the selected articles are diligent in presenting contextual background and all underline its importance. This took shape either in a dedicated section (e.g., Compion et al., 2022; Wang & Han, 2023) or within discussion sections (e.g., Enjolras, 2021; Katz-Gerro et al., 2015). We find this approach significantly assists in understanding the motivation behind the research and its findings. Such contextualization equips the researchers with, and explains to the reader, valuable insights into the social, cultural, economic, and political milieu surrounding the studied topics.

Comparative research can respond to big research questions in the field. There is a tendency, both in quantitative and qualitative articles, to study the evolution of the sector and its actors’ structures and behaviors. In parallel, there is a compelling imperative to examine civil society and the third sector’s responses to multifaceted and contemporary challenges. These challenges encompass critical global issues such as the climate crisis as well as the increasing complexities of governance systems. Comparative exploration is key to understand the sector's adaptability and its distinctive role in addressing pressing concerns on both local and global scales.

Concluding Remarks

A criticism to the selected articles is that despite their comparative approach and placement in Voluntas, they do not necessarily contribute to some of the questions around comparison in the field that started in the 1990s. We would not suggest that it is a requirement that all comparative studies hash out the trajectory of comparison in civil society and third sector studies. However, we would have expected that some of the seminal pieces published in the 1990s would be a starting point or foundational to some of the comparative questions across the ten articles. Wang and Han’s (2023) paper is relatively more active in engaging with Voluntas’ articles, while many of the chosen articles rely on citations from journals within the fields of sociology, political science, and area studies, such as Asian, African, or European studies. The ten articles also had limited connection with social origins theory. One reason for this is the difficulty of incorporating the distinct "regimes" of social origins theory into a cross-national quantitative model, as the theory tends to require tracing the historical development of institutional features. In this sense, Enjolras’ (2021) work is noteworthy as it attempts to link concurrent and cross-national explanatory variables to the institutional–structural features of civil society.

This introduction to the virtual issue sought to summarize the early years of Voluntas which brought about a rich body of comparative third sector research and its debates. Many of these authors were in direct conversation with each other. Clearly this was supported by editorial leadership—as at times there were “comments on” pieces (Ragin, 1998; Steinberg & Young, 1998), and “responses to” (Fowler, 1998), complemented by editorial statements and articles by editors reflecting on comparative research (Brandsen & Simsa, 2016; Simsa & Brandsen, 2021). In the 1990s and then again 2016, there were deliberate exchanges among our colleagues about cross-national comparative research (centered on definitions, classifications, measurement and theory building and testing) in Voluntas that we underline here, given their contributions to moving debates (and the field) forward. We hope that this virtual issue and the two recent pieces on comparative research published in Voluntas in 2023—Salamon, Haddock and Toepler’s (2023) article in the methodological special issue and Anheier’s (2023) recent editorial essay—might generate continued exchanges on the pages of Voluntas.