A randomized controlled trial of geriatric screening and surveillance was undertaken on a practice population of 295 patients aged 70 years or more over a two-year period. In the screened group (145 patients) many social problems were found and a total of 380 medical conditions were reported during the study period, 144 (38 per cent) of which were previously undetected. Conditions found most frequently involved the circulatory, musculoskeletal and nervous systems; 67 per cent of the conditions found were manageable, half being improved and the remainder resolved completely.The screening programme was found to increase the use of social and health services but it did also decrease the expected duration of stay in hospital.Independent assessment of patients in the study and control groups at the end of the two-year period showed that the screening programme had made no significant impact on the prevalence of socio-economic, functional, and medical disorders affecting health.We formed the firm impression that the study patients were made more comfortable (by control of pain) and less disabled, although there was no unequivocal objective evidence of this. They were, however, kept independent for longer.The findings are discussed and a model of geriatric care is suggested combining conventional management on demand with comprehensive screening to identify the high-risk patients on whom care might need to be focussed.