This book undertakes an in-depth examination of the diversity in international approaches to the navy-coastguard nexus. It considers the evolving global maritime security landscape and the emergence and proliferation of maritime law enforcement agencies-collectively referred to here as coastguards-performing peacetime constabulary duties alongside navies. Through a cross-regional study of various countries worldwide, including those in Asia and Europe, this book reveals that there is no one optimal, one size fits all organizational structure. Instead, there is a wide array of drivers that influence a nation-state's maritime security architecture and its organizational approach to managing security at sea, or broadly speaking, securing its national maritime interests.