From October 2006 to May 2008, The WorldFish Center coordinated a ZoNéCo project to provide support to the Southern and Northern Provinces for decisions about how best to manage the sea cucumber fishery around La Grande Terre. We collected data during underwater population surveys, questionnaire-based interviews with fishers and processors, and landing catch surveys. A core aim was to furnish the Provinces with ‘ballpark’ estimates of the abundance and density of commercially important sea cucumbers on 50 lagoon and barrier reefs. Analysis and synthesis of the ecological and sociological data provide the basis for informed recommendations for fisheries management. Counts of trochus and giant clams on the reefs allow us to also describe the general status of those resources. We propose 13 recommendations for management actions and fishery regulations and advocate an adaptive management approach. This multidisciplinary study should serve as a useful template for assessing other fisheries, and we provide a series of generic ‘lessons learnt’ to aid future programmes.