OBJECTIVE Description of the activities of daily living and the use of care in relation to several determinants in persons aged 85 years and over. METHODS Cross-sectional survey. METHODS General population from the city of Leiden, the Netherlands. METHODS A representative sample from the inhabitants aged 85 years and over of the city of Leiden was enrolled. A physician visited 239 'oldest old' (response rate 83%) at their places of residence, in 1991/'92. Data were obtained on health (joint disorder, cardiovascular disease, diabetes mellitus, Parkinson's disease; disorders in cognition, eyesight, hearing; limitation of mobility), self care and household activities in daily living and the use of care (informal care by neighbours or family, (geriatric) home help, district nurse, private help). Statistical analysis was performed by non-parametric tests and logistic regression. RESULTS Of the 'oldest old' 111 (46%) lived independently, and 67 of them (28% of the total group) had no professional help. Almost all 'oldest old' had at least one health disorder. In all, 129 women (77%) and 43 men (61%) had restrictions in basic and (or) instrumental activities of daily living. These restrictions were strongly related to disorders in cognition, vision and mobility, less related to chronic disease and not related to hearing disorders. Restrictions in the activities of daily living were also related to the living condition. This relation was particularly strong for women. Men living without a partner were more likely to be institutionalised. Among the 'oldest old' who lived independently, restrictions in the activities of daily living were related to the use of care, with the exception of privately organised care. CONCLUSIONS One out of four persons aged 85 years and over lived without professional help. Marked differences between the sexes were found for the interrelation between activities in daily living and the use of care.