Background: The health needs of people with intellectual disabilities have recently received increasing attention. Method: Based on a review of the 2003 literature, this paper presents an overview of our knowledge on physical, mental and social well-being in this group. Results: Physical well-being is threatened by handicap-related conditions, syndrome-related health problems and lifestyle characteristics. Conclusion: Gaps in knowledge include insufficient evidence on health disparities, the lack of comparability of data on the prevalence of ill heath, lack of expertise in relation to communication problems and the fact that all knowledge is based on research in developed countries, while people with intellectual disabilities in developing countries face the same or even greater health problems. Recommendations concerning evidence, education and empowerment are formulated.