Dian Fossey was an American primatologist and conservationist who is best known for her work with mountain gorillas in Rwanda. She was the subject of the 1988 film Gorillas in the Mist, which was based on her 1983 book of the same name. Fossey's research focused on the behavior and social structure of the endangered species of APE known as the GORILLA (GORILLA), which she studied for 18 years in the Virunga Mountains of Rwanda. Her work helped to bring attention to the plight of the species and to the need for conservation efforts to protect them from poaching and habitat destruction.