Evidence accumulates that better management of coastal biodiversity outside of protected areas will be necessary to halt current trends of depletion. Japanese satoumis are human-influenced coastal seas that are both productive and rich in biodiversity. Satoumi has gained interest within and outside Japan as a field-tested approach to conciliate sustainable ecosystem use and conservation of biodiversity. This paper provides a review of new reports on field implementation of satoumi in Japan. An analysis identifying key institutional features that foster satoumi is provided as well. A great variety of active conservation measures that do not rely on the exclusion of human influence to manage biodiversity are being assessed. Some are centuries-old, such as river basin forestry, some more recent such as seagrass transplants or artificial tidal flats. Crucial to their success are the involvement of local communities and the voluntary contribution of significant labour by ecosystem users, mostly fishers. These contributions from fishers’ communities are an internalisation of the costs of conservation by the economic activity that benefits from it. Rather than a cultural specificity, the latter appears to rest essentially on collective ownership of territorial use-rights, strong local collective structures that enforce the community’s interest, and the availability of active conservation measures as options to contribute to biodiversity management through manual work in the ecosystem. It is argued that as the effectiveness of these approaches becomes demonstrated, they should be adequately accounted for in international agreements and targets for biodiversity conservation.