The socio-economic monitoring programme was designed to quantify, over a period of a year, three of the principal outcomes from the fishery – fish production, the economic surplus generated and its distribution between the main actors. It was recognised that these outcomes would be influenced by the existence or absence of reserves (through their effect on resource status) but that this was only one influence among many. Attempting to quantify the impact of reserves through comparisons of villages was therefore inappropriate. The purpose of the SEMP was to develop a greater understanding of the outcomes themselves, the types of relationships that can exist between them and some of the mediating factors in each village.