Much of the discussion surrounding the definition of the Sustainable Development Goals (SDGs) and the post-2015 global development agenda has contextualized sustainable development within the framework of ‘transformation’, specifically prioritizing concepts such as equity, security, justice, and rights. While these debates correctly discussed power imbalances and relational obstacles to human development they have remained abstract because they focused only on the international level. In this regard, discussions have not adequately examined mechanisms that facilitate or block the emergence of sustainable development as a political priority, nor do they address specific policy proposals to link environmental justice to human development strategies. This book contends that human and environmental security should be framed in terms of transnational discussions rather than being limited to general international debates in order to examine both governance challenges and potential policy mechanisms that can effectively address environmental security issues that cross national boundaries. The chapters in this volume undertake an empirical examination of the relationships between human and environmental security, cross-border exchanges, and regional integration. They address the relationships between international norms, transnational human and environmental security issues, and the regionalization of governance in different parts of the world as the book includes comparative analyses as well as case studies from Europe, Asia and the Americas. The chapters originally published as a special issue in Globalizations.