The Galápagos archipelago has a natural environment that is unique on earth and it is the “cradle of evolutionary biology”. Both of these facts led to the declaration of the archipelago as a national park of Ecuador and the first UNESCO World Natural Heritage Site. This status is in danger, however, because the archipelago has lost its isolation. The uniqueness of the natural environment has been threatened for a long time by introduced animals and plants. Some original species have already become extinct. Nature conservation and research are battling this threat with large-scale projects: extermination of introduced animals coupled with breeding and reintroduction of endemic species, which has already succeeded on some islands. However, an end to the problems, reaching from the tiniest parasite to the growth of population and tourism, is not in sight. This is why, in the future, nature conservation will still play a leading role in preserving the World Natural Heritage Site of Galápagos.