19.1 Introduction

Individual behaviour is a cornerstone of sustainability transitions: while systemic changes in technology and policy are vital, the role of individuals and small groups, such as families, initiatives or teams at work, in adopting sustainable practices and technologies, shaping and following social norms and supporting or opposing policy measures is equally critical. For sustainability transitions to be successful, it is necessary to address both macro-level changes and the micro-level behaviours and choices that play a role in both driving and hindering change. This applies whether individuals are organised in civil society groups (Smith, Reference Smith, Verbong and Loorbach2012) or acting separately as consumers or electorates with practical consequences nonetheless (Jackson, Reference Jackson2004).

The study of sustainability transitions, their evolution and emergence, has been an interdisciplinary field from the very beginning. Transition processes have always been characterized as fundamental changes in socio-technical systems. Thus, the ‘social’ side of transitions and the interaction of (technological) innovations with governance processes but also wider society has been a constitutive part of transition research. This in turn means that what people do, how individuals act on their own or in collectives, what they think and what influences their thoughts and actions are in principle an inherent part of transitions research. Individuals also play an important role in the collection of data on transitions, with interviews as a central research method in this field of research (Hansmeier et al., Reference Hansmeier, Schiller and Rogge2021). Thus, the perspective of the individual strongly shapes our view and knowledge on transitions.

In practice, however, the socio-technical sustainability transitions literature has had difficulty accommodating especially individual-level perspectives, principally because the field focuses on what may be thought of as meso- and macro-level processes, rather than the micro-level of individual psychology (Upham et al., Reference Upham, Bögel and Dütschke2019; Upham et al., Reference Upham, Bögel and Johansen2020). At the same time, failure to account for individual behaviour and leaving this behaviour ‘black-boxed’ as ‘emergent’, means that key processes are potentially neglected. Hence while connecting levels of analysis is challenging (Köhler et al., Reference Köhler, Geels, Kern, Markard, Onsongo, Wieczorek, Alkemade, Avelino, Bergek, Boons, Fünfschilling, Hess, Holtz, Hyysalo, Jenkins, Kivimaa, Martiskainen, McMeekin, Mühlemeier and Wells2019), it is nonetheless of value to do so. In this chapter we explain why individual behaviour matters for transitions.

The APA Dictionary of Psychology (American Psychological Association, n.d.) defines behaviour as ‘an organism’s activities in response to external or internal stimuli, including objectively observable activities‘, but also ‘introspectively observable activities (…), and nonconscious processes‘. When transition scholars refer to behaviours, they tend to adopt partly similar definitions. Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021, p.587), for example, use a definition from the Cambridge English Dictionary: ‘The way a person acts in a particular way in a particular situation or under particular conditions.’ Both definitions link behaviour with certain conditions (‘external or internal stimuli’, ‘particular situations or (…) conditions’). However, while the first explicitly states that behaviours also include internal processes such as forming an opinion, this is not the case for the second. This difference is an important distinction between transition studies and behavioural studies, such as psychology, which place more emphasis on these internal behaviours.

The repeated pointers to activities in both definitions show that the study of individual behaviour is closely linked to the study of actors and agency. Other than referring to individuals, the concept of actors is generally broader and more closely linked to the concept of roles. Roles describe distinctive sets of behaviours associated with an actor (Wittmayer et al., Reference Wittmayer, Avelino, van Steenbergen and Loorbach2017 and cf. Chapter 17 in this handbook). Similarly, in contrast to behaviour, agency is a broader concept defined as the capacity to act intentionally (de Haan & Rotmans, Reference de Haan and Rotmans2018). Thus, agency has a component of direction and combines the acts themselves as well as the potential for acting by referring to capacity. Behaviours, however, are not necessarily intentional, but also include habitual or conditional reactions in certain situations.

Often, psychological approaches on behaviours differentiate between types of behaviour on a continuum, with routines and habits at one end and deliberative behaviour at the other end (Defila et al., Reference Defila, Di Giulio and Ruesch Schweizer2018; Verplanken & Aarts, Reference Verplanken and Aarts1999; Whitmarsh et al., Reference Whitmarsh, Poortinga and Capstick2021). Routinized or habitual behaviours are typically triggered by (external or internal) stimuli and occur repeatedly, often regularly. These types of behaviours are to some extent automated and often following routines, such as a morning shower – triggered by getting up and always using a specific water temperature and a certain soap. For example, they usually cycle, but take the bus in case of bad weather. At the other end of the continuum lie behaviours that are once-off and deliberative such as decision-making, especially where there is an investment of significant resources or where there are significant impacts. Such behaviours are often the result of longer processes that involve other behaviours, such as gathering information or considering costs and benefits. This type of behaviour is, for example, relevant for the decision to switch from a conventional vehicle to an electric one, or to adopt a car-free lifestyle.

All types of behaviour along this continuum are relevant to sustainability transitions because the establishment of the new system relies on decisions by a variety of individuals in different roles: policymakers need to adapt regulations, managers in firms need to invest in new products and households need to adopt these products. The new system is then likely to lead to new routines, which, in turn, influence all individuals in the changed system. This leads us to the standing acknowledgement that behaviours are embedded in contexts. They are influenced, supported or challenged by the current system. While this is more obvious for habitual behaviour as stimuli-driven, this also applies to more deliberative behaviours which are influenced by social norms, personal attitudes and available resources. The deliberative behaviour of, for example, buying an electric car ten years ago required a lot of resources and motivation, is much easier now, but still innovative in 2024 (at least in some countries) and is likely to be the ‘normal’ decision in 20 years’ time.Footnote ¹

However, transitions research has not frequently investigated the role of individuals and behaviour. According to Hansmeier et al. (Reference Hansmeier, Schiller and Rogge2021), the focus on actors and agency has increased significantly in transitions research in the past years, however, theory development in sustainability transitions on the role of behaviour and individuals is still ongoing and an emerging field. Hansmeier et al. (Reference Hansmeier, Schiller and Rogge2021) found that as of 2016, only 20% of papers from transitions research targeted actors (and their networks), while the share was nearly 50% in the period 2016–2019. Important contributions have been made recently by a review by Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) and by several papers involving Upham and Bögel (Bögel & Upham, Reference Bögel and Upham2018; Upham et al., Reference Upham, Bögel and Dütschke2019; Upham et al., Reference Upham, Bögel, Klapper, Kašperová, Teerikangas, Onkila, Koistinen and Mäkelä2021), building on earlier work by Upham et al. (Reference Upham, Lis, Riesch and Stankiewicz2015). The review by Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) provides a classification of behaviour types that we make use of below. The work by Upham and Bögel reviews the use of psychology and social practice theory in the transitions literature (Bögel & Upham, Reference Bögel and Upham2018, updated as Upham et al., Reference Upham, Bögel, Klapper, Kašperová, Teerikangas, Onkila, Koistinen and Mäkelä2021) and explores different ways of conceptually and methodologically connecting micro-level social psychological processes with larger scale transitions concepts.

Here, the focus will correspondingly lie on individuals and behaviour, extending previous accounts on actors and agency with additional perspectives and regularly drawing on neighbouring fields of research – psychology in particular.

19.2 Historical and Thematic Development

Studying the social or societal side of socio-technical systems has typically implied analysing social forms of action (Bögel & Upham, Reference Bögel and Upham2018). Individual behaviour, as a separate and smaller research focus, has been mainly discussed in relation to consumption behaviour and everyday life, described below, building close links with the increased interest on the role of the individual as a ‘consumer’ or ‘user’ in the broader field of science and technology studies (STS) (Köhler et al., Reference Köhler, Geels, Kern, Markard, Onsongo, Wieczorek, Alkemade, Avelino, Bergek, Boons, Fünfschilling, Hess, Holtz, Hyysalo, Jenkins, Kivimaa, Martiskainen, McMeekin, Mühlemeier and Wells2019). An introduction to work in the latter vein can be found in the nine-fold co-design typology of Hyysalo and Johnson (Reference Hyysalo and Johnson2024).

A focus on users and consumers links with research on sustainable consumption, which is a field of research in its own. One of the prominent approaches has been to build on ‘practice theory’ (Warde, Reference Warde2005), which has also regularly been applied in transition studies (Kaufman et al., Reference Kaufman, Saeri, Raven, Malekpour and Smith2021 and also Chapter 6 in this book). Practice theory takes practices, that is, usually certain classes or groups of repeated or routinized behaviour, as a starting point, for example meal preparation and eating. It then moves on to identifying the factors that shape, uphold or potentially change these practices, typically including three types of factors such as material, image and skill. Material refers to existing structures, available equipment or objects, while image captures symbolic and communicative meanings and implications; finally, skills relate to individual competences involved in the practice (cf. Shove, Reference Shove2010 for exemplifying). A focus on practices is typically related to a focus on daily behaviours and how they are embedded in (social) context and structures and may extend to changes in these behaviours. The acting subjects are usually individuals in their roles as consumers or users and less often individuals involved in practices of changing or shaping the system itself.

The role of users and consumers has received significant attention in the last one to two decades also in other streams of research such as in innovation studies or studies on technology adoption.Footnote ² There has been a shift away from viewing consumers and users in a passive role of ‘adopting innovation’ or ‘accepting technologies’ into a more active one. In this active role, consumers are seen as individuals that shape or trigger developments in technological innovation by stating needs and driving, or at least refining, technological or sectoral developments (cf. Chadwick et al., Reference Chadwick, Russell-Bennett and Biddle2022). Examples here are the early phases of the German energy transition where many early investors came from fields outside the energy industry, such as farmers setting up windfarms or solar PV fields, or even earlier developments in Denmark where electricity users, including individuals and collectives, pushed forward windfarm installations (Schot et al., Reference Schot, Kanger and Verbong2016). This related field of research suggests that, in sustainability transitions, roles of individuals are changing from using and consuming to being entrepreneurs or suppliers within newly emerging niches or even regimes (Wesche & Dütschke, Reference Wesche and Dütschke2021).

Building on this line of thought and developing it further for the study of sustainability transitions, a paper by Schot et al. (Reference Schot, Kanger and Verbong2016) describes several roles of users and consumers in transitions and the corresponding relevant behaviours.Footnote ³ These behaviours are categorized according to roles of groups of individuals and differ according to the phase of a transition. In the early niche-focused phase, typical actors and behaviours driving the transition include

1. 1. user-producers who are involved in inventing and experimenting with technological or social innovations and enabling new routines to emerge and

2. 2. user-legitimators who shape the meaning, purpose and rationale of niche innovations by building and sharing narratives.

In the following acceleration phase, in which the interaction between niche and regime starts to change the current regime, they identify

1. 3. user-intermediaries who are involved in networking between niche actors and actors outside the niche for scaling up innovations and

2. 4. user-citizens who engage in changing the current regime to enable niches to grow.

Finally, in the stabilization phase of the new regime, there exist

1. 5. user-consumers who embed innovations in their lifestyle and adopt their lifestyle to the innovations and thus support their diffusion.

All five roles are associated with specific behaviours, such as designing technological applications, generating ideas or concepts, communicating with others or using and applying innovations. The behaviours identified by Schot et al. (Reference Schot, Kanger and Verbong2016) allude to the differentiation between more habitual and more conscious behaviour as defined above.

This continuum between routinized and deliberative behaviour also influenced the work of Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) who conducted a review on the transitions literature through a behaviour lens. The authors differentiate between four types of behaviours: reflective, automatic, strategic and everyday behaviour. Their categorization takes up conceptualizations found in the literature rather than observed phenomena in transitions. The first two types of behaviour were identified based on papers with a stronger focus on micro-meso perspectives. Reflective behaviour connects with conscious implementation – on the deliberative side of the behaviour continuum. Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) find that studies on reflective behaviour are typically engaged with changing behaviour and acknowledge bounded rationality and the drivers and barriers to behavioural change. A relatively high number of papers was identified in this field by Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021), but many of them not highly cited.

Automatic behaviour covers both habits and embedded behaviour triggered by situational cues, matching the routinized or habitual side of the behaviour continuum in psychological approaches. Beyond habits, Kaufman et al (ibid) found this literature to also emphasize the role of heuristics and biases in relation to behavioural choices. The reviewed studies suggest that interruptions are necessary to change these types of behaviours. Research advocating for nudges to foster transitions, that is, designing situations in a way that the probability of the desired behaviour increases, was also grouped under this approach. While fewer papers were identified than on reflective behaviour, they were more frequently cited. The other two types of behaviour, strategic and everyday, refer more to the meso-level and thus are less attached to the micro level and the individual. Strategic behaviour is seen as intentional action by collective actors, such as companies or agencies, niche actors or incumbents, to achieve a benefit for their innovation or retaining current technologies, usually in a competitive context. Thus, this perspective addresses interactions within networks of (collective) actors. Everyday behaviour covers what was described as practices earlier. Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) emphasize that from the literature it is not clear whether purposeful or directed change of practices by external actors is possible given the complexity of conditions shaping practices.

Additional streams in the transition literature that partially focus on behaviour but have a greater focus on collectives and the meso-level includes the research on social movements and civil society organizations (Köhler et al., Reference Köhler, Geels, Kern, Markard, Onsongo, Wieczorek, Alkemade, Avelino, Bergek, Boons, Fünfschilling, Hess, Holtz, Hyysalo, Jenkins, Kivimaa, Martiskainen, McMeekin, Mühlemeier and Wells2019). Research on social movements looks for instance into grassroot innovations and how they create consumer demand or drive innovations from outside the traditional sector or branch as citizens (Köhler et al., Reference Köhler, Geels, Kern, Markard, Onsongo, Wieczorek, Alkemade, Avelino, Bergek, Boons, Fünfschilling, Hess, Holtz, Hyysalo, Jenkins, Kivimaa, Martiskainen, McMeekin, Mühlemeier and Wells2019). While individual behaviour is usually not the starting point of the analysis, its importance is acknowledged (e.g. Hossain, Reference Hossain2016). Another part of literature on social movements analyses the role of individuals in challenging or providing legitimation to transitions, that is, resisting or promoting change. In line with what Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) categorized as strategic behaviour, this research does not only investigate individuals and collectives as drivers of transitions, but also as showing resistance. Examples are citizen-driven initiatives supporting wind farms and owning them through cooperatives versus local action groups opposing windfarms.

Furthermore, a stream of research which has been established in the literature is the one on the role of intermediaries in transitions, mainly building on Kivimaa et al. (Reference Kivimaa, Boon, Hyysalo and Klerkx2019). Intermediaries are defined as ‘actors and platforms that positively influence sustainability transition’ (Kivimaa et al., Reference Kivimaa, Boon, Hyysalo and Klerkx2019, p.1072) through a variety of behaviours such as ‘linking actors and activities (…) or by connecting transition visions and demands of networks of actors (…)‘. Intermediaries are discussed in more detail in Chapter 18 of this handbook.

A recent stream of literature, not only in the field of transition studies but also related to it, conceptualises energy citizenship to capture engagement with an energy system in transition. It typically refers to different types of engagement, such as citizens as consumers, prosumers, prosumers, political activists, members of energy communities, and thus also points to the diversity of relevant behaviours of individuals in transitions (Schlindwein & Montalvo, Reference Schlindwein and Montalvo2023) and the emergence of new practices (Ryghaug et al., Reference Ryghaug, Skjølsvold and Heidenreich2018). Although the topic of energy citizenship is inherently related to a transition, it has not yet become a major topic of transition research; no paper applying the concept could be found in the main journal ‘Environmental Innovation and Societal Transitions’ until summer 2024. Nevertheless, this literature seems promising for theorising individual behaviour in a transition context.

Finally, classic disciplines that focus on behaviour and the individual have extended their scope. For instance, in environmental psychology, claims have been made to link research more strongly to transformative approaches (Wullenkord & Hamann, Reference Wullenkord and Hamann2021). In her influential book on ‘The Great Mindshift’ also Göpel (Reference Göpel2016), self-identifying as a political economist, makes the case for the role of individuals and their behaviour by stating ‘(…) the source of intentional change is human thinking, feeling and acting. Socio-ecological systems are created, ordered and stabilized through human decision making (…)’ (p. 50f). She draws on the Multi-level perspective from transitions research (cf. Chapter 2 in this handbook) and adds a ‘mini level’ representing the individual level to the usual MLP-structure (p. 47). This matches with the development that researchers from environmental psychology have extended their understanding of environmental behaviour as sustainable consumption to including so called ‘other directed behaviour’ or ‘public-sphere behaviour’ such as taking part in protests or other voluntary work on environmental issues (Capstick et al., Reference Capstick, Nash, Whitmarsh, Poortinga, Haggar and Brügger2022).

19.3 Empirical Application: The Individual and Its Behaviour in the Energy Transition

Sustainability transitions have commonly been studied with a focus on one or several sectors in which society is organized. These range from energy and transport to medicine and food production. The greatest empirical focus, both for overarching transition processes as well as for the individual and behaviour in transitions, has been on the energy sector (Upham et al., Reference Upham, Bögel and Johansen2020). In the following, we hence focus on examples applying a behavioural perspective to the energy transition as a large-scale change in one socio-technical system in which individuals and their behaviour have played a crucial role.

Looking at energy transition processes provides several opportunities to further illustrate the role of individuals and behaviour. The energy transition refers to the transformation of the energy system of a community, region, country or association of states (such as the EU) in such a way that it produces little or no greenhouse gas emissions. There are three basic approaches to achieving this, which can complement each other: consistency, efficiency and sufficiency. They involve replacing fossil fuel-based energy production with renewable energy (the consistency approach), achieving the same results with less energy (the efficiency approach) or reducing overall demand (the sufficiency approach) and they all affect and are affected by individuals and their behaviour.

Superficially, the consistency approach has little impact on the consumer side, as the required energy is still provided, only by different generation mechanisms. However, the fact that energy production from wind and PV has been able to achieve large impacts and develop to a stage where it is economically competitive has been driven by individuals and organisations outside the established energy sector (Schot et al., Reference Schot, Kanger and Verbong2016). Moreover, consistency approaches have serious implications for the supply system, changing business models and triggering new industries. This requires a wide range of individuals to change their current behaviour by investing differently, developing offerings along newly developed supply chains, or changing production patterns of energy generation technologies (see Fricaudet et al., Reference Fricaudet, Parker and Rehmatulla2023 as an exemplary study). Furthermore, moving on to generating electricity from wind or sun instead of coal and gas implies adapting to a fluctuating electricity production due to the weather. While this can be done technically by improving the interconnectedness with other geographical areas, or by providing energy storage, it can also be achieved through behavioural change which is known as demand side management. Demand side management means that demand for energy is adapted to the supply side, that is, increasing production in industrial processes or starting energy intensive household processes when ample energy is available (e.g. Wesche & Dütschke, Reference Wesche and Dütschke2021 on the different roles for organisations). Thus, demand side management is strongly connected to changing practices or – through a more individual lens – to adapting routines and habits (e.g. Solbu et al., Reference Solbu, Ryghaug, Skjølsvold, Heidenreich and Næss2024 on low-income households).

Efficiency as a strategy is mainly technology-oriented and refers to increasing the output without increasing inputs, for example, by using more efficient appliances, insulating buildings, moving to more efficient heating systems or changing patterns of consumption to less resource intensive products. Thus, this field of research is much about technology acceptance, but also includes broader transition-related topics such as studying the networking behaviours of actors in the heating transition (Wesche et al., Reference Wesche, Negro, Brugger, Eichhammer and Hekkert2024) or the discourse of households as users and installers around metering systems which are supposed to enable more efficient resource use (Rohracher & Köhler, Reference Rohracher and Köhler2019).

In addition to consistency and efficiency, sufficiency is increasingly discussed as a pathway to reach the goals of the energy transition. Sufficiency refers to systematically changing structures and behaviours in a way that leads to lower levels of resource and energy use will keeping levels of well-being (Sandberg, Reference Sandberg2021). In terms of electricity use, this could mean using fewer devices; in terms of energy more broadly, it could mean reducing the amount of space heated or switching heating systems to lower temperatures and cooling systems to higher temperatures, thus, finding other ways to achieve thermal comfort levels. Thus, as can be seen from the examples, the sufficiency approach has a strong behavioural component in changing habits and routines, but also broader practices and the use of different decision-making strategies. Systematic research on sufficiency is still in its infancy and therefore a rare topic also in terms of individuals and their behaviour in transition studies (see Solbu et al., Reference Solbu, Ryghaug, Skjølsvold, Heidenreich and Næss2024 as a rare example).

Other specific areas of interest linking individuals and their behaviour to the energy transition concern processes within organisations and the individuals embedded within them. This includes differences in strategic behaviour and motivations in transitions (Scherrer & Rogge, Reference Scherrer and Rogge2025), decisions between multiple technologies (Scherrer, Reference Scherrer2023) and the behaviour of individuals as employees or managers in companies (Upham et al., Reference Upham, Bögel and Dütschke2019). Scherrer and Rogge (Reference Scherrer and Rogge2025) presented a first analysis of the former for the decarbonisation of heavy-duty vehicles and Upham et al. (Reference Upham, Dütschke, Schneider, Oltra, Sala, Lores, Klapper and Bögel2018) exemplified the latter for the case of hydrogen fuel cell applications.

In addition, the study of behaviours that slow down the transition is also highly relevant – phenomena include, for example, what is referred to in the literature as rebound effects (Galvin et al., Reference Galvin, Dütschke and Weiß2021; Sorrell, Reference Sorrell2015), that is, when the use of more efficient technologies does not lead to the expected reduction in demand or when the increased share of green electricity leads to higher consumption levels. Unlike the case of technology diffusion, this is a behavioural effect that is usually not purposeful or rooted in resistance to the transition, but nevertheless undermines achieving the sustainability goals. For instance, Dütschke et al. (Reference Dütschke, Galvin and Brunzema2021) portray the variety of individual engagements with roof-top PVs in households and the heterogeneous outcomes related to it.

19.4 Ongoing Debates: Connecting Macro and Micro Analysis in Transitions Research

In this section we discuss debates relating to how to address the behaviour of individuals within or alongside the analytic frames used in sustainability transitions. This is one instance of structure versus agency and macro-micro debates that have accompanied the history of modern social and behavioural sciences. While we have shown that micro, individual-level processes have been relatively under-studied in sustainability transitions frameworks, the broader field of sociology has long recognised the importance of understanding macro-micro linkages, to understand (and particularly model) social phenomena (Berk, Reference Berk2006; Raub et al., Reference Raub, Buskens and van Assen2011; Schillo et al., Reference Schillo, Fischer, Klein, Goos, Hartmanis, van Leeuwen, Moss and Davidsson2001). Researching this linkage raises questions of how particular micro and macro level processes and conditions influence one another, of the directionality in cause and effect and of the ways in which these linkages can be studied. For transitions, it also raises the issue of where the research focus of the field both lies and should lie. These questions go to the heart of what the transitions field is and what transitions researchers want that field to be – what research questions, approaches, theories, frameworks, epistemologies and ontologies are viewed as constituting the field.

A key question that this requires scholars to negotiate is thus the extent to which, and how, agency, individual and collective behaviour, is and are determined or influenced by macro-level structures – including social norms and culture, technologies and infrastructures and economic and political systems (Gibbs, Reference Gibbs2017). Arguably, the transitions literature has implicitly taken a rather radical, pro-structural position on this question, by focusing mainly on structural change, to the neglect of the micro-level processes, choices and behaviours involved. As said, in social studies more generally, there is recognition of the roles of both macro structures and individual agents in relationship with one another. Indeed the structuration theory (Giddens, Reference Giddens1984) that Geels (Reference Geels2002) used to explain the differing degrees of societal embeddedness of the niche, regime and landscape in his multi-level perspective is an explicit attempt to reconcile macro- and micro-level phenomena (agents reproduce external structures by following internalised rules, a version of Bourdieu’s (Reference Bourdieu1977) theory of habitus). For further detail on micro-macro linkages in the social sciences generally, see Raub et al. (Reference Raub, Buskens and van Assen2011), who provide a short review of the work of the many authors who have sought to connect levels of analysis to understand social phenomena.

Social practice theory (Warde, Reference Warde2005), as mentioned above and drawing heavily on Bourdieu (Reference Bourdieu1977), is one of the approaches that contributes to delineating these relationships in depth, though again more leaning towards the structural side (see also Chapter 6 in this book). Instead, in psychology and behavioural economics, there has been a strong presumption that behaviour change research should aim to identify the decisive factors operating principally at the individual level, and that understanding these factors will support an anticipatory, predictive and interventionist approach to social change. These different positions are partly related to academic traditions: while sociologists and political scientists tend to emphasise structures, psychologists and behavioural economists tend to emphasise individual autonomy in decision-making and behavioural choices, even if those choices might be considered flawed from some external perspective. Moreover – and this is where the main problem lies in this context – much of the most popular social psychological or behavioural research in recent decades has focused on intra-individual processes. This is epitomised in theories such as the theory of planned behaviour (TPB) (Fishbein & Ajzen, Reference Fishbein and Ajzen1980) and the norm activation model (Schwartz, Reference Schwartz1977), which recognise factors external to individuals but nonetheless focus on individual, subjective experience to explain behaviour.Footnote ⁴ Bosnjak et al. (Reference Bosnjak, Ajzen and Schmidt2020) report that as of April 2020, the TPB had been investigated in more than 4200 papers referenced in the Web of Science, which means it is one of the most frequently applied theories in the social and behavioural sciences. It is not surprising that some sustainability transitions theorists want to keep a clear emphasis on structures external to individuals, and on collective, social phenomena rather than on the individual. At the same time, structure-focused research faces greater challenges in producing (seemingly) precise quantitative results, which has led to a lower societal impact compared to behavioural economics (Fuchs et al., Reference Fuchs, Debourdeau, Dütschke, Fahy, Garzon, Kirchler, Klöckner and Sahakian2025).

Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) call for a combination of perspectives instead to advance transitions and to ensure that relevant dynamics at different levels are not underestimated. This means recognising, considering and above all addressing the role of structures as well as the complexity of factors influencing socio-technical change, as in practice-driven approaches to everyday behaviour, by also considering strategic behaviour. At the same time, however, they take the view that the individual level should not be neglected – in its habitual constraints, but also with its capacity for reflective behaviour to adapt habits and routines and to support or resist to system change (ibid.).

Of other authors working in this space, Göpel (Reference Göpel2016) emphasises the role of individual mindsets for sustainability transformations; Huttunen et al. (Reference Huttunen, Kaljonen, Lonkila, Rantala, Rekola and Paloniemi2021) call for a pluralistic understanding of agency; and Upham et al. (Reference Upham, Bögel and Dütschke2019) set out ways in which micro-macro connections may be made in research practice: via nested or connected studies at different scales, using different methods; use of bridging concepts that have both individual and social dimensions (e.g. narratives or social representations); and study of individuals within collectives, such as organisations or movements.

Geels (Reference Geels2020, p. 3) strongly questions the endeavour to bring individual-level processes into transitions analysis, saying: ‘(…) methodological individualists suggest that only individual human beings should be considered as actors with the capacity to act (…) Such a conceptualisation is practically unworkable, however, for socio-technical transitions.’ Geels (Reference Geels2020) argues that too many individuals are involved in transitions and that collective actors are thus a key focus. Yet those seeking to bring social psychological insights into transitions perspectives are not arguing for methodological individualism, nor are they arguing against the importance of studying collective actors. The matter of there being too many individuals to account for is again not a very convincing argument: rarely does social psychology reason from the experience of single individuals alone, and transitions analysts themselves deal with a plethora of technologies, companies and contexts. In fact, the transitions literature often reasons from individual cases or a small number of these, which entails its own issues of generalizability. What matters in all of this is correspondence between the purposes of a study, its research questions, methods, theories or frameworks and the claims being made. What we have sought to explain above is that bridging macro-micro schisms is a longstanding tradition in the social sciences (Ritzer, Reference Ritzer2008), and that studying the role of individual behaviour in transitions is just one instance of this endeavour – but a worthwhile one.

19.5 Summary & Conclusions

Summing up, the perspective on individuals and behaviours has not been a core topic of transitions research, which has traditionally focused on mid-range theories. However, as the field becomes increasingly differentiated and with rising interest in details and complexities and the increasing awareness that actual sustainability transitions have not moved forward at the pace and the impact level needed, interest in the individual level is increasing. This also leads to a higher interest in building bridges to other disciplines with a longer history on these topics, first of all (social) psychology, but also other fields such as behavioural economics.

In the future, further conceptual development, especially to making links with already more established concepts and streams of research in transitions research is needed, as continued by authors such as Kaufman et al. (Reference Kaufman, Saeri, Raven, Malekpour and Smith2021) or Göpel (Reference Göpel2016). This could also contribute to overcoming some of the debates around the field or to move further by creating more detailed knowledge. More specifically, potential avenues for future research include:

• Future research should enhance our understanding of individuals and their behaviours by adopting a multi-actor approach, recognizing people not just as consumers, but also as decision-makers, public activists and policymakers (Upham et al., Reference Upham, Bögel and Dütschke2019).

• Studying the interrelation between individual and collective behaviour is crucial to understanding how individual actions influence collective strategies at micro, meso and macro levels.

• Analysing the diverse behaviours within multi-actor systems during different phases of transitions is important, including the roles of advocates, intermediaries, incumbents and those impacted by transitions, while also exploring how transitions become normalized and their effects on individual behaviour.

• Research should further explore how social disparities, inclusiveness and diversity impact individual behaviour in transitions, with a particular focus on underexplored factors such as gender influences.

This chapter ends on a reflexive note, as research on sustainability transitions is often, at least implicitly, normative in terms of the goals transitions seek to achieve; however, this context also raises a potential pitfall: a tendency towards an instrumental interpretation of behaviour and its transformation, which the field needs to be cautious about.