High poverty levels in western Kenya that are manifested in malnutrition and poor health prevail yet the region is endowed with high agricultural biodiversity like African Leafy Vegetables (ALVs). The vegetables have high micronutrient content, medicinal properties, several agronomic advantages and economic value yet their potential in alleviating poverty and ensuring household food and nutrition security in the rural areas has not been exploited. Despite all the above advantages, these vegetables have been neglected and face several constraints hampering optimal production such that if the situation is left unchecked it may result in loss of this biodiversity. It is because of this that a study was conducted with the objectives of documenting the diversity of African Leafy Vegetables and to collect indigenous knowledge on production, agronomic and cultural practices in three communities of Western Kenya. A survey was conducted between January 2002 and March, 2003, in six districts in Western and Nyanza provinces representing the Luhya, Luo and Kisii communities. A structured questionnaire was administered to eighty purposively sampled respondents distributed in the ratio of 30:20:30 for Luhya, Luo and Kisii communities respectively. One focus group discussions per community was held and two key informants per community were interviewed. Over 90% of the respondents indicated that there was an increase in the cultivation of African Leafy Vegetables. Ten African Leafy Vegetables were found in the three communities representing eight botanic families. All the communities cultivated the ALVs at a subsistence level in home gardens, with organic sources of manure and under an intercrop system. Broadcasting was practiced by 20%, 40% and 60% of the respondents from the Luhya, Luo and Kisii communities respectively. Harvesting was done by first uprooting at thinning then ratooning. The major constraints facing production of African Leafy Vegetables included lack of quality seed, pests and diseases, drought, poor marketing strategies and lack of technical packages. In conclusion, the study showed that all the three communities studied had a high diversity of cultivated African Leafy Vegetables covering eight botanic families; respondents in all the communities cultivate African leafy vegetable in a subsistence, home gardening, intercrop system where the use of chemical fertilizers and chemicals was minimal and the major constraints of production of African Leafy Vegetables included, poor quality seed, drought and poor marketing systems and infrastructure. The identified species should be promoted and improved as commercial crops.