The International Marine Mammal Project is a proud part of the Earth Island Institute, a non-profit, tax deductible organization founded in 1982. The Earth Island Institute has a long and active history in dolphin-related causes. In 1986, through the International Marine Mammal Project, EII organized a campaign to urge U.S. tuna companies to end the practice of intentionally chasing and netting dolphins with purse seine nets, and to adopt "Dolphin Safe" fishing practices to prevent the drowning of dolphins in tuna nets. This campaign included a consumer pressure, litigation, and revisions of the US Marine Mammal Protection Act. In 1990 a major breakthrough was achieved and the first companies pledged to become dolphin-safe. Today 100% of American tuna have become verifiably dolphin safe. Through the International Monitoring Program, the Earth Island Institute regularly inspects tuna companies to insure consumers that the tuna they buy is truly "dolphin safe."

Earth Island Institute is an umbrella organization with has more than 60 projects working for the conservation, preservation, and restoration of the Earth.