This book is the outcome of a rather unique conjunction of circumstances that prevailed at the World Bank Institute in Washington, DC, in the years from 2008 to 2012. There and then, a talented group of young staff in the Governance and Leadership Unit, working in the atmosphere of creativity and the supportive authorizing environment provided by the renewal the World Bank Institute was undergoing, began putting their minds together to explore a number of questions few others at the World Bank had addressed. What are the types of constraints that conspire to derail otherwise sensible policies? When can these constraints prevent a reform process or a project from achieving its declared objectives? How can these constraints to change be unlocked? Under what conditions do individuals and organizations engage in collective action, and when does this lead to the sort of lasting institutional change that is conducive to sustainable development? These were the sorts of questions the team probed tirelessly over three years. In line with the World Bank Institute’s global learning and training mandate, this book was initially conceived as an instructor’s guide, with games and exercises, and addressed to those charged with equiping practitioners with the analytical tools and practical exercises to navigate the treacherous and often murky waters of policy reform. Upon closer scrutiny, it dawned upon the team that few books explain these tools to lay readers, and even fewer had ventured to jump the fence and reach out to practitioners. It is to attempt to address these gaps that the idea of this book in its present form first emerged.