Across Europe, the number of co-housing initiatives is growing, and they are increasingly receiving attention from administrators and professionals who hold high expectations for urban liveability. Is co-housing a marginal idealist phenomenon, or the urban middle class' answer to the current housing crisis? And has the development of theoretical insight and research kept up with the actual expansion of co-housing as a practice? These questions were raised during the first European conference on co-housing research, which took place in Tours, France, in March 2012. Both the conference and this book aim to move beyond case-studies, and to look more particularly at the implications and wider perspective of the current co-housing trend. Using the specific vocabulary of different disciplines and geographic regions, the contributions to this book analyse the underlying thinking behind, and the expectations projected on, diverse models of collaborative housing. The authors are aware of the qualities of contemporary co-housing, but they go beyond advocacy to investigate the conditions under which co-housing can be successful as a strategy for housing provision; can offer solutions for sustainable urban development; or indeed can contribute to involuntary or intentional gentrification. This book was originally published as a special issue of the Journal of Urban Research and Practice.