In 1995, a study found that the socioeconomic benefits from a legalized commercial harvest of sea turtle eggs in Ostional (Costa Rica) were substantial and widely recognized by Ostional residents. Legal and administrative structures ensured community participation in and control of resource use, and evidence indicated support for community-based conservation (CBC) was high. In 2004, the study was repeated to assess how perceptions of the egg harvest might have changed over time. There were continued high levels of support for conservation and positive perceptions of the project's impacts on the economy, environment and community. Some explanations for impact rankings have changed, with greater emphasis on the importance of conservation and awareness of how this is achieved, greater animosity towards one government agency and greater concern about the impacts of tourism on the egg harvesting project. Between surveys, a variety of social, political and economic changes have occurred. The CBC concept has been further refined and critiqued; by examining a CBC project over time, this paper considers the durability and flexibility of the incentive, legal and administrative structures associated with a successful example of CBC.