WHO SAGE-INDEPTH is conducted in partnership with the International Network for the continuous Demographic Evaluation of Populations and their Health in developing countries (INDEPTH), with support from the US National Institute on Aging. The goals are to generate needed health data on older adults in lower income countries, to use common measurement strategies across health and demographic surveillance systems (HDSS) to examine ageing and adult health, and to develop methods to link routine surveillance data and longitudinal survey data. The full SAGE instrument was implemented in 2007/08 in a random subset of respondents in South Africa (Agincourt), Ghana (Navrongo), and India (Vadu) HDSS fieldsites, resulting in a total sample of almost 1500 individuals. A shortened version of SAGE was implemented in four Asian and four African INDEPTH fieldsites with a resulting sample of over 40,000 respondents.