Geriatric efforts have prophylactic effects on further reduction of functional ability at every link in the therapeutic chain by means of interdisciplinary qualitative and quantitative assessment which establishes goal and plans which lead to coordinated action. This results in early diagnosis of multiple pathology, reduction of polypharmacy, confidence on account of good information, continuity on account of coordination between primary and secondary sectors, simultaneous efforts, early interruption of the cascade effect which results in production of helpless patients. By means of clinically controlled trials, effects have been obtained on a number of recently discovered diagnoses requiring treatment, unnecessary medication is withdrawn, conditions of rehabilitation, functional ability, quality of life, employment of bed-days, institutionalization and mortality. It is necessary to state that this is the only age group where the effect is obtained without further expense or where the effort has even resulted in economic savings. In Denmark, research is required as regards how prophylactic health visits to the elderly can best be carried out in all communities, the risk situations (death of a spouse, removal, illness) which require immediate increased efforts and research into how offensive geriatrics is to be established, how rehabilitation is ensured for healthy and sick elderly patients and research into the occurrence and treatment of the five geriatric giants (immobility, instability, incontinence, intellectual reduction and iatrogenesis). More Danish controlled trials are required of the individual components in and the total function of geriatric assessment and rehabilitation and the significance of personal choice when the functional ability is such that dependence on care by others is inevitable and, finally, the conduct and expenses of various arrangements.