The societal discussion on the switch to long-term sustainable emission levels is dominated by the idea that technological improvements can solve the problem without any need for changes of lifestyle. Others oppose this belief and instead point to an urgent need for sacrifices such as reduced air and car travel. The notion that lifestyle changes would imply reduced quality of life is so widely embraced that it may in itself be an obstacle to bringing about a political change towards reduced greenhouse gas emissions. But the limited amount of research that has examined the actual relationship between emission reductions and quality of life has not come to any clear conclusions. This report looks into an exciting and unexplored “third way” in the climate discussion, where we ask whether a greater focus on human welfare could, quite simply, become a driver towards sustainable development rather than an obstacle. The report begins (Chapter 3) by giving an account of the various theories about what characterizes a “good life” and how it can be measured. Chapter 4 describes the various societal and individual factors that have been proven to influence individual well-being. We also look at the small field of research that has explicitly investigated the links between well-being and greenhouse gas emissions. The report’s contribution to this field of research is presented in Chapter 5 and consists of an analysis of three areas that we think are of particular interest. The first area of interest is urban development, which is of crucial significance in enabling people to reduce their greenhouse gas emissions and in attaining a high level of well-being. Research in this area shows that the choice of modes of transport and commuting distance, besides the impact on greenhouse gas emissions, have a major impact on well-being and stress levels. We also examine what a change in consumption mix, towards more services and less material goods, would mean for greenhouse gas emissions, and for human well-being. The third key area identified is individuals’ use of time, particularly in prioritising between work and leisure time. We conclude (Chapter 6) with a discussion of how the links between households’ greenhouse gas emissions and well-being could be analysed using practice theory. Practice theory makes practices (e.g. commuting, holiday travel and cooking) the central objects of the analysis. The climate impact of a certain practice can be analysed by studying the consumption that it generates. This also makes sense from a behavioural point of view as it enables a matching of emissions with each practice’s impact on people’s quality of life. The last chapter (Chapter 7) identifies issues for future research that we believe may be important in contributing to new understanding in this area of research.