The author spent six weeks in Zaire early in 1975 to get first-hand experience both of mountain gorillas, in the Kahuzi Biega and Virunga national parks, and of bonobos (pygmy chimpanzees) in forests south of the Zaire river. As a result he believes that, Tor the mountain gorillas, the enlargement, already planned, of the Kahuzi Biega park is important to ensure that population's viability, and also that thought should be given to introducing new blood into the Virunga population, which may already be suifering from inbreeding. For the bonobos he suggests that, if investigation confirms the view that the Salonga National Park is not a good area for them, the Lomako-Bolombo region should be considered for a bonobo reserve. Dr MacKinnon is a member of the IUCN Survival Service Commission's Primate Group and has made major studies of the orang-utan.