The incidence density of hip fractures in the population of Amsterdam, aged 70 years and over, was studied according to the type of residence. In 1989, 655 patients were admitted to nine hospitals within Amsterdam for a hip fracture. Postal codes were used to classify the residence of the population and the hip fracture cases as independent, home for the elderly or nursing home. Stepwise logistic regression was used for data analysis. The risk of hip fracture increased with age and was 1.7 times higher for women than for men. In the age group 70-74 years the relative risk (RR) was 7.6 for those in homes for the elderly and 5.8 for those in nursing homes, when compared with the independent elderly. This RR was approximately 1 for those in homes for the elderly aged 85 years and over. However, in nursing homes the RR was still 2.8 in the age group 95+. We concluded that, despite protective measures against falls, the institutionalized elderly are at greater risk of hip fracture than the independent elderly of the same age and sex. This higher risk is especially apparent in the 'younger' age groups.