Recent years have seen a surge of interest in 'the commons' based on a simple yet radical idea: great improvements in production and management could be achieved by reducing barriers to knowledge exchange and power-sharing. Ranging from meadows, forests and parks to language, open-source software (FLOSS and Blockchain) and 3D printers, the commons are distributed or common property resources/infrastructures that are self-managed by their user communities. While acknowledging the significant contributions that can be made through commons-based peer production, this book provides a critical examination of the commons with the aim of contributing to their long-term sustainability. In particular, the book examines the relation of Blockchain to the commons by illustrating the case study of the Commons Stack. Drawing on a range of interdisciplinary ideas and methodologies, the book argues that there are a number of economic and social barriers that are obstructing the wider reproduction of the commons. Problems with access to capital and training, the lack of entrepreneurial and managerial skills and the absence of institutional support from governments, larger co-ops and NGOs are some of the external difficulties facing the commons today. Meanwhile, localism, gated communities, vested interests, atavism, traditionalism, ideology, conflict, neo-conservatism and techno-elitism represent some of the internal contradictions inherent in the commons. Through overcoming these contradictions, the ultimate goal is to transform capitalism into the postcapitalism of the commons: the creation of a social economy self-organised around the commons. This book provides vital reading for anyone interested in the commons, from economics, techno-politics and across the social sciences.