Book chapter to appear in H. Bulkeley, V. Castán Broto, M. Hodson, and S. Marvin (eds) Cities and Low Carbon Transitions, London: Routledge LIVING LABORATORIES FOR SUSTAINABILITY: EXPLORING THE POLITICS AND EPISTEMOLOGY OF URBAN TRANSITION James Evans and Andrew Karvonen The University of Manchester INTRODUCTION Creating a more sustainable society is increasingly an urban challenge (Pincetl 2010). Upwards of fifty percent of the world’s population currently dwells in cities, and this figure is forecast to rise dramatically over the coming decades (Grimm et al. 2008). Cities both concentrate the activities that produce carbon emissions, and suffer disproportionately from their negative impacts such as air pollution, temperature increases, water shortages, and increased flooding. Given this, cities are increasingly being looked to as sites to develop long‐lasting solutions to climate change (Hodson and Marvin 2007). This chapter focuses on the use of ‘living laboratories’ to drive innovation in sustainable urban development. The types of spaces designated as living laboratories are highly variable, from a single plot of underdeveloped land to a degraded waterway, from a clogged transportation corridor to a completely new city. Further, a wide variety of organisations – notably universities, government bodies, and private companies – are using the term in an unapologetically boosterish manner to develop and market their own approaches to sustainability. Their enthusiasm is underpinned by two assumptions. First, living laboratories are real life experiments that promise to produce more useful knowledge and second, they are highly visible interventions with the purported ability to inspire rapid social and technical transformation. Taking a series of examples, we consider the epistemological and political implications of living laboratories, asking whether such experiments really do hold the potential seeds of change, as this literature suggests, or whether there are other motivations at work. The chapter concludes with a discussion of role of the living laboratories approach as a form of experimentation in relation to theories of transition and sustainable urban development. LABORATORIES AND KNOWLEDGE GENERATION The word ‘laboratory’ implies an epistemology; it is a way to know the world. Laboratory studies scholars have furnished well‐known accounts concerning the exceptional qualities of laboratories as privileged spaces that channel and accentuate the power of science (e.g., Latour and Woolgar 1979, Knorr‐Cetina 1981, Lynch 1985). Because they are purposefully separated from the lived world, they allow variables to be isolated and carefully manipulated in order to test hypotheses (Knorr‐Cetina 1995). The material practices that take place in laboratories involve the enculturation of natural objects, breaking them down into constituents that can be examined under conditions dictated by the exacting demands of the experiment rather than the unpredictable whims of nature. In this sense, 'laboratories create enhanced environments where it becomes possible to see things not visible elsewhere' (Henke