The chapter presents an outline of the most important framework regulations under present day law of the sea with regard to marine environmental pollution. It outlines the modern history of the law of the sea and very briefly the negotiations leading to the adoption of the LOS Convention. The chapter explores key aspects of the LOS Convention concerning the protection of the marine environment, that is, the duty of states to protect the marine environment from pollution; the rights of states to combat pollution from different sources; and global and regional cooperation.