This book gives a brief review of current development models and governance of urban sharing platforms, and looks into the economic efficiency of a novel market transaction model of sharing economy, which has been accelerated by high-density urban population and the Internet technology. With an aim to solve current problems featuring excessive competition, waste of resources, security risks, and unfair competition, this book delves into the two governance models in accommodation sharing platforms and bike and car sharing platforms and puts forward a multi-dimensional collaborative governance model that involves the participation of enterprises, the government, and the community. Under such a model, the platforms may utilize their own key technologies to implement supervision and solicit feedback; the government may resort to tax regulation and reallocating shared space to mitigate the negative externality effect and promote fair competition; and the community, as the basic unit of a city, may play its part through on-site participation and real-time feedback.