Southern Malawi is characterized by the Rift valley and the Shire Highlands, which are dominated by the Zomba and Mulanje plateaux, and the Kirk Range. These mountainous areas are a source of various rivers and streams, which support small-scale integrated agriculture-aquaculture systems (IAA). The IAA systems were introduced to Malawi in 1986 by the WorldFish Center when a range of IAA technologies were developed and disseminated to farmers. The most common IAA system consists of fishponds, vegetables, fish, rice and irrigated maize. This system is practised by over 2,000 farmers in southern Malawi. The number of farmers practising this system has grown by 25% per year over the past 5 years because of the impact that this system has on household food security, income and environmental sustainability.