CHAPTER 1: INTRODUCTION The Intergovernmental Panel on Climate Change has shown that stabilizing the increase of global mean temperature below 2°C relative to pre-industrial levels entails a fundamental global challenge (IPCC 2014). With billions of people vulnerable and hundreds of millions at extreme risk from weather-related disasters, climate change poses a great threat to individuals as well as to social and political stability. Climate change has been described by Nobel peace prize winner Wangari Maathai as a "life or death" threat conducted in "a new global battlefield" (Vidal 2009:2). Continuing with business as usual is associated with unfathomable risks and great uncertainties for human life (IPCC 2014). Increased greenhouse gas emissions have been a major cause of the very large late 20th-century warming (Crowley 2000). The sources of these emissions are anthropogenic (i.e., human) activities. The industry sector (especially electricity and heat generation), agriculture, forestry, and other land use industries have contributed two-thirds of global emissions (IPCC 2015). Transportation contributes 14% and buildings contribute 6% of all emissions. In Sweden, 18% of greenhouse gas emissions comes from buildings, an amount equivalent to the transportation sector (Informationscentrum för hållbart byggande 2018). Clearly, a continuation of business as usual in the housing sector is not sustainable. According to leading advocates, a transition to low carbon housing will require very energy efficient buildings on a wide scale, both in developed and developing countries (International Energy Agency 2017). From a climate change perspective, efficient buildings are deemed to be crucial since they lower the overall demand To capture the interrelationships of technical and social elements in the process of mainstreaming, these interrelationships are studied as 'socio-technical' phenomena. A socio-technical perspective entails an approach to the construction and development of buildings emphasizing that technological choices, such as adopting passive house standards and practices, depend on how technologies are embedded in social, political, and economic organizations (Rohracher 2001). This means that institutions and technologies in the housing sector are understood to develop closely in parallel (Nykamp 2017), and advocates of energy efficient buildings adapt their strategies in line with changing social and technological circumstances in the housing sector (Guy & Shove 2000). In socio-technical research, a key interest is how emerging technologies, such as passive houses, co-evolve with institutional change. A study of mainstreaming as situates the thesis within previous research on sustainable buildings in general and passive houses in specific with a focus on socio-technical perspectives. The chapter presents strengths and weaknesses of previous research, how previous research is used, and what this thesis can contribute with in this context. Chapter 4: Theoretical framework presents the theoretical perspective...