This chapter addresses the question: whatformsof migration can be distinguished? This topic is closely tied to the issues addressed in the previous chapters, concerning why and how people migrate. Central to the discourse on migration forms—also called categories, types, or flows—lies another important question: whoaremigrants? This chapter dives into these questions. While the topic of migrant typologies itself would merit its own full-fledged analysis, this is beyond the scope of this chapter. The reflections herein rather seek to summarise some of the main arguments and questions pertaining to the debates on categorisation in migration studies.

After a brief introduction of how the word ‘migrants’ is used, the chapter moves on to discuss how different migrants and journeys are categorised into specific forms of migration. By briefly discussing the use of categories and recent discourses on categorisation in migration studies, this chapter sets the stage for the next three chapters of this book, as these delve into the subjects of labour migration, family migration, and humanitarian migration more specifically. Finally, the chapter offers a few reflections on the logic behind the choice of migration forms in focus both in this book and in the taxonomy of the Migration Research Hub.

1 To Be (Labelled) a Migrant

Tazzioli (2019) notes that “some people are labelled and governed as ‘migrants’”. This is an important remark, as it sheds light on the difference between migrant as a category of self-identity, and migrant as a label which others apply when referring to people who move or have moved. This chapter primarily focuses on the latter of the two understandings, though the interrelation between the two is not to be ignored. While most acknowledge the need for human categories for the purposes of analysis and governance, such categorisation also raises ethical concerns (see e.g. Bakewell, 2011; Raghuram, 2021). Is it morally correct to define people by only one aspect of their character, identity, or life? The migrant label, or any sub-category or migration form, only refers to a specific—current or past—activity. The act of moving or crossing an international border may indeed be a crucial aspect or turning point in a person’s life, yet it remains one sole activity, and not necessarily an identifying or key characteristic.

The study of migration has nonetheless become a field on its own. So, too, have the fields of politics, policies and jurisdictions concerning people who migrate. It is impossible to do justice to the heterogeneity of people and their lives through any migrant category. Yet, in order to analyse, govern, and even understand the phenomenon of migration, we need to reify the abstract process of human mobility into set categories. To rephrase the quote above, this chapter holds that some people are, and need to be, labelled, governed, and studied as migrants. Central to this understanding stands the constant acknowledgement that the word ‘migrant’ remains a crude simplification of any person who migrates.

2 The Multitude of Migration Forms

Building on the premise that people usefully may be categorised as migrants, the next central question is: which different forms of migration can be identified? The different words used to distinguish one form of migration from another are regularly the objects of academic scrutiny, and most migration scholars would agree that we cannot capture the fluidity and complexity of any migration through these specific tags (see e.g. Crawley & Skleparis, 2017; Castles et al., 2014; Dahinden, 2016; Fussell, 2012; Talleraas, 2020). Nevertheless, to study migration in its various shapes and modalities, we need to understand the differences between flows. The factors used to distinguish one type of migration from another comprise a range of parameters, including—but not limited to—the geography of the migration, the reasons or drivers of migration, the characteristics of the migrants, the migrants’ aims, and the infrastructures and mechanisms shaping the journeys. Moreover, the migrants’ legal status at the outset of, during, and after their journey place them into specific categories (Kubal, 2013), which also provide them with different legal rights and duties. This implies that the group, or migration form, migrants belong to, and thus how they are analysed or governed, can shift over time and en route.

A leading understanding in migration studies highlights the political geography of migration journeys by differentiating between two key forms: internal migration and international migration. The former refers to migration within a country and the latter to migration across state borders. Within each of these, migration drivers are often used to distinguish between two sub-groups: those who are forced to move and those who migrate voluntarily. A central line of criticism in migration studies refers to the impossibility of stringently dividing between forced and voluntary migration. This often-used dichotomy risks undermining the potential ‘spectrum’ of drivers and experiences inherent in any migration journey (Erdal & Oeppen, 2018, p. 981). A related discussion concerns whether refugees are—or should be—understood as migrants. While one side of the dispute sees all who have changed their country of residence as migrants, the other categorises those who have moved to seek international protection as a separate group, holding that refugees should never be included in the migrant category (see e.g. Carling, 2017). These discussions underscore the potentially grave consequences—both analytically and politically—of how we distinguish between different sub-forms of migration. As the international legal frameworks concerning refugees provide them with a distinct set of rights, it is especially important to apply these labels with particular care.

The categorisation of particular migration forms can be undertaken by different actors with various purposes, such as border control agencies, human rights activists and political parties. Such categorisation into different forms often involves defining migrant groups on the basis of a specific variable. Illustrative examples include: ‘unskilled migrants’ or ‘unaccompanied minors’, which draw on the migrants’ characteristics; ‘labour migrants’ or ‘lifestyle migrants’, which highlight the drivers or motivations of the migration; or the term ‘boat migrant’, which refers to the means of travel. While categorisation is a useful tool for states and researchers alike, many have argued that any “cookie cutter approach” to migration involves overgeneralisation (Gupte & Mehta, 2007; Talleraas, 2020). The line of criticism concerning “methodological nationalism” in migration studies also highlights the need to critically assess how nation-state logics and categories are reiterated in research (Brubaker, 2013; Dahinden, 2016; Wimmer & Glick Schiller, 2002). State structures serve to manage migration while also producing exclusionary understandings of ‘unwanted’ (see e.g. Anderson, 2013) or victimised (see e.g. Schenk, 2021) migrant groups. Lack of reflection concerning migration form labelling may risk reproducing hegemonic power relations and “essentalised ideas” (Dahinden et al., 2021, p. 538). When deciding which label to apply, or when distinguishing one migration form from another, it is necessary to evaluate the dominant categories applied, and avoid conflating categories of analysis with categories of practice (see e.g. Van Hear, 2012). This is particularly important as the migration form labels applied impact how people are understood, encountered, and treated (see e.g. Erdal & Oeppen, 2018; Ottonelli & Torresi, 2013).

3 A Systematic Literature Review of Migration Forms

This chapter has sought to reflect on the categories of migration forms and the practices of using them in migration studies. Based on brief examination of the questions of who are the migrants? and what forms of migration can be distinguished?, two key lessons may be drawn. First, when studying people as ‘migrants’, we need to remember that they may have ‘little else in common’ (Carling, 2017). While it is useful to distinguish migrants from non-migrants – for practitioners, policymakers, and researchers alike – the label itself does not reflect who people are, how they identify and what they do. Second, the categorisation of migrants into sub-groups is a valuable tool, both for analytical purposes and for the provision of rights. Yet, we must acknowledge the broad spectrum of experiences inherent in any migration journey, and continually consider the social, political, and analytical repercussions of the labels we use to distinguish some people from others.

The ensuing chapters of this book provide extensive literature reviews of a specific collection of migration forms, including labour migration (Chap. 6), family migration (Chap. 7), humanitarian migration (Chap. 8), lifestyle migration (Chap. 9), student mobilities (Chap. 10), and irregular migration (Chap. 11). The chapters offer insights into the development of these research fields, and include overviews of key findings, research approaches and methodologies. The selection of the specific forms included in this book is based on recent work with the establishment of the Migration Research Hub. To create a typology of migration forms for this online tool, for the purpose of categorising and systematising research on migration, a range of experts and scholars have been consulted. Through discussions, a typology of migration forms has been developed where three existing and widely used migration forms are found to - theoretically - encapsulate many of the other categories that are widely applied in analytical and policy work. These three migration category labels are based on the driving force behind that particular migration. Migration drivers is understood as key lines of division between migration flows, and we differentiate between labour, family, and humanitarian migration in the effort to systematise the Migration Research Hub taxonomy, and the ensuing literature reviews.

In line with this aim, the three next chapters include discussions on a variety of ‘sub-forms’ of migration. In particular ‘labour migration’ is understood to include ‘high-skilled migration’ and ‘low-skilled migration’; ‘family migration’ includes ‘transnational families’ and ‘marriage migration’, and; ‘humanitarian migration’ encapsulates ‘refugees’, asylum seekers’, ‘internally displaced people’, ‘victims of trafficking’ and ‘unaccompanied minors’. The following three chapters reviewing literature on migration forms thus include types that cannot be captured within the categories of labour, family or humanitarian migration. These forms were nevertheless included here as it is possible to distinguish a distinct discourse on each form, consisting of elaborate bodies of theoretical and empirical research (i.e. Chaps. 9, 10 and 11 on lifestyle, student and irregular migration). The broad array of literature included in the three first chapters nevertheless illustrate how these three key forms, the sub-forms they encapsulate and other name-given forms, are more complex than their labels might suggest. The range of research referred to reflects the multiple factors that influence the spectrum of migration processes and showcases that any act of migration can be called by different names, depending on the reasons underlying the need for categorisation.

The reviews in the ensuing chapters primarily draw on literature available through the Migration Research Hub database. An important aim of these chapters, as with the database itself, is to enable researchers and practitioners to grasp the complexities of knowledge on types of migration. To this end, the Migration Research Hub taxonomy system systematises knowledge on a greater range of specific migration forms than is included here, and presents this in an accessible way. The migration forms that are included in the taxonomy are: environmental migration, family and marriage migration, health-related migration, high-skilled migration, internal displacement migration, internal migration, irregular migration, LGBTQ migration, labour migration, lifestyle and retirement migration, low-skilled migration, multiple migration, refugee migration, asylum seeker migration, return migration, roots migration, short-term and circular migration, transnational migration, unaccompanied minor migration, student mobility and trafficking. While the taxonomy system is not designed to capture the plurality of, or flexibility in, migration experiences, the aim is for it to be used as a research and policy tool to discover knowledge on different migration forms. In line with the ever-evolving nature of migration and migration research, the migration forms included in the taxonomy is likely to be updated and change with time. The current full list of migration forms and definitions are available through the Migration Research Hub taxonomy.