Frontiers in International Environmental Law explores how law and legal scholarship has responded to some of the most important oceans and climate governance challenges of our time. Using the concept of the frontier, each contributor provides a unique perspective on the way that we can understand and can shape the development of law and legal institutions to better protect our marine environment and climate system, and reduce conflicts in areas of legal uncertainty. The authors show how different actors influence legal development, and how legal transitions occur in marine spaces and how change influences existing legal regimes. They also consider how change creates risks for the protection of vulnerable environment, but also opportunities for creative thinking and better ways of governing our environment.