Chumbe Island Coral Park Ltd (CHICOP), established in 1991 as the first managed marine park in Tanzania, has become an international test case for sustainable private marine conservation funded by ecotourism. The experiences, problems and achievements of CHICOP are described, in particular drivers and incentives for committed on-site MPA management in the legal and institutional environment of Zanzibar. The employment of local fishers as park rangers proved cost-effective and facilitated partnership with local fishing communities, as did Environmental Education (EE) programs for local schools and communities. Risks for private investors remain high though due to limited long-term security of tenure of leases and contracts.