Coconut-based agroforestry systems have a central role in livelihoods on Malo Island, in the South Pacific. This complex pluri-specific plantation provides the family with both food and cash income, thanks to the association in space and time of food crops (mainly root crops) and cash crops (coconut, cacao and vanilla). Since the year 2000, vanilla has been developing on the island as a new cash crop. Farmers try to adapt their production systems to include it. Some of them chose to do so by associating vanilla with their main cash crop, coconut. A survey of these innovative practices and their economic results was conducted in 2005 and this resulted in economic modeling of this new agroforestry system. Based on this study, the process of diversification of production inside small farming units is analysed