In recent years, with the HIV epidemic in Kenya stabilising and treatment programs in place, questions have arisen as to whether sub-populations traditionally seen as at most risk of HIV are still the main sources of new infections. The importance of "knowing your epidemic" (KYE) and "knowing your response (KYR)" has become evident to target and improve HIV responses. The World Bank, UNAIDS and other agencies have initiated a series of HIV epidemiological and response syntheses in Africa, Asia and Latin America to KYE and KYR.