The growth of aquaculture - now the fastest growing food production system in the world - is increasingly attracting private investment. Much of this investment, however, is in larger enterprises and input services such as feed, seed and processing. Little is targeted at smallholder farmers who, as a result, continue to face constraints in accessing finance, technology and markets. In 2010, WorldFish set out to explore the business case for investment in smallholder aquaculture by examining several donor funded projects. Research found that investments in smallholder farmers and their organisations can be commercially viable, creating economic as well as social and environmental benefits.