Design Governance focuses on how we design the built environment where most of us live, work, and play and the role of government in that process. To do so, it draws on the experience of the Commission for Architecture and the Built Environment (CABE), a decade-long, globally unique experiment in the governance of design. This book theorises design governance as an arm and aspiration of the state; tells the story of CABE, warts and all, and what came before and after; unpacks CABE's 'informal' toolbox: its methods and processes of design governance; and reflects on the effectiveness and legitimacy of design as a tool of modern-day government. The result is a new set of concepts through which to understand the governance of design as a distinct and important sub-field of urban design.