The surveys reviewed use a variety of methodological approaches which illustrate the different types of questions addressed by health surveys and show how different aspects of survey methodology relate to the usefulness and limitations of the studies. The aims, methods and results of over 50 studies are discussed under the headings : general measures of health and sickness, the nature of disease, assessment of needs, use of services, effects and side effects of care, acceptability of services and organisation of care. Methodological issues, ethics and the potential of health surveys are also discussed.