Ocean Conservancy is a nonprofit environmental advocacy group based in Washington, D.C., United States. The organization seeks to promote healthy and diverse ocean ecosystems, prevent marine pollution, climate change and advocates against practices that threaten oceanic and human life.

Marine conservation activism is the efforts of non-governmental organizations and individuals to bring about social and political change in the area of marine conservation. Marine conservation is properly conceived as a set of management strategies for the protection and preservation of ecosystems in oceans and seas. Activists raise public awareness and support for conservation, while pushing governments and corporations to practice sound ocean management, create conservation policy, and enforce existing laws and policy through effective regulation. There are many different kinds of organizations and agencies that work toward these common goals. They all are a part of the growing movement that is ocean conservation. These organizations fight for many causes including stopping pollution, overfishing, whaling and by-catching, and supporting marine protected areas.