Can psychological and practice theory approaches to environmental sustainability be integrated? As a psychologist and a social theorist who collaborate in interdisciplinary research, we followed the debate in this journal between Shove (2010;, Whitmarsh and colleagues (2011), andWilson andChatterton (2011) with interest. The question of whether psychological and practice theory approaches to promoting sustainable behaviour and social change can be integrated for effective policy making is crucial for our work.Initiating the debate, Shove (2010) argued that current UK strategies to mitigate climate change, based in psychology and economics, are limited because they assume that an individual's behaviour is chosen and that choice is driven by attitudes. Noting that social practices are configured by institutions, she argued that contemporary 'rules of the game' must be eroded and existing institutions challenged for more sustainable practices to be established.In response, Whitmarsh et al ( 2011) argued that psychology does not view behaviour as 'chosen' or straightforwardly attitude driven, and called for an integration of practice theory and psychological approaches. This call was rejected by Shove (2011) because these approaches have incommensurable methods of enquiry, meanings of evidence, and research agendas.Finally, Wilson and Chatterton (2011) took a pragmatic approach. They argued that, because practice manifestations are behaviours, practice theory insights enhance psychological ones, providing policy makers with additional ways of thinking about environmental sustainability.We do not agree with Shove (2010; 2011) that the differences between practice theory and psychological approaches make them incommensurable. Similarly, unlike Wilson and Chatterton (2011), we believe that using multiple models is not necessary for broadening the conceptualization of issues of sustainability. Rather, like Whitmarsh et al (2011), we believe that an integrated approach is necessary to achieve environmental sustainability because both individual action and social structures must change. In this commentary we outline Binder's (2008;2012) Model of Recursive Cultural Adaptation (MORCA), an integrated model that has proved useful for understanding how unsustainable practices can be modified.The MORCA draws on a range of disciplines, including psychology, sociology, and philosophy, to explain why and when social practices are defended, modified, or transformed. These include James's (1890) theoretical work on habits, Bourdieu's concept of habitus, and Sharrock and Dennis's (2008) Wittgensteinian analysis of rules that demonstrates we do not necessarily follow them.A central proposition of the MORCA is that practices exist and are transmitted between practitioners because they are useful, allowing them to function effectively. As a result, practices are shared by a community of practitioners. Further, practices and their meanings are learned and their enactment (ie, their behavioural component) becomes habitual with time. As a ...