Proyecto Caguama (Operation Loggerhead) partners directly with fishermen to ensure the wellbeing of fishing communities and sea turtles alike. Fisheries bycatch can jeopardize both fishermen’s livelihoods and endangered species such as the loggerhead turtle. Nesting exclusively in Japan, this population has declined precipitously due largely to severe bycatch throughout its range from the South China Sea to the California Current. Since 2003 we have identify regionally important bycatch hotspots and developed bycatch solutions with fishermen from Mexico, Japan, and Hawaii. We engage key fisher leaders through participatory research, locally resonant media including comics, murals and festivals, and trinational exchanges that offer fishermen personal experience of the Pacific-wide impacts of their local bycatch. Strategies range from market-based solutions to gear technology, and all are built upon capacity-building for fishing organizations and government agencies. ProCaguama achieves widely renowned conservation success building on the fisher networks of the Grupo Tortuguero de las Californias and the Sea Turtle Association of Japan.