Achieving sustainability is perhaps the single-most important task for our generation. In the face of a looming climate disaster, calls for the sustainable use of the worlds resources are getting louder. As the sea covers more than 70 per cent of the earths surface, this holds even more true for the use of ocean resources. Despite its vastness, the sea has often been a securitised and politicised space, where the concepts of sustainability and security meet at sea in the form of a myriad of important contemporary issues. In this volume, we set out the intersection between sustainability and security alongside the security-development nexus, and examine these issues under four dimensions of security: economic security, ecological security, human security, and traditional security. Within sections dedicated to each of these we explore both theory and practice by offering cases alongside a conceptual discussion, and in so doing cover topics ranging from the Blue Economy and the net-zero agenda, to natural disasters and climate change, from food security and the future of Small Island Developing States, to the geopolitics of the Arctic. This book takes a birds eye view, connecting the dots between these issues of security and sustainability, and ending with scenarios for the future with policy-making in mind. This volume presents a timely and compelling argument that policymakers and scholars need to come to terms with the intersection of sustainability and security at sea. The editors detail a clear and insightful conceptual approach for grasping the simultaneity and interplay of security and sustainability concerns that will give inspiration to further research in the field. Chapter contributors convincingly illustrate aspects of this approach across regions, scales and sites of political engagement from port cities to the UN. A must read for students, researchers and practitioners of ocean politics. Elana Wilson Rowe, Research Professor at the Norwegian Institute of International Affairs (NUPI) Too often issues of security and sustainability at sea have been studied in narrow terms. This volume makes a critical contribution the literature by unpacking the interconnections and interdependence between these two vitally important issues. Robert McCabe, Assistant Professor and Director of the MA Maritime Security Programme at Coventry University. "In this timely publication, an international set of contributors portray a rich array of views on the oceans, security and sustainability for the reader. Of particular value is how the security-sustainability nexus runs through the chapters to emphasise the ever-growing importance and relevance of this interplay. Francois Vre, Professor Emeritus of Military Science and Research Coordinator at the Security Institute for Governance and Leadership in Africa (SIGLA), Stellenbosch University.