On account of the ageing of the population, the general practitioner will be more and more solicited to care for old people. The determinations of the degree of dependence of the elderly person is more a global bio-psycho-social concept than the classic view of the curative medicine. Two scales of evaluation of the state of dependence--the Katz scale and the Old People Aid scale--are commonly used in Belgium. Are they valid and do they reflect the actual recourse for aid and care? To answer the questions, this article refers to a study realized in the french community of Belgium about people older than 65 years. The analysis of the dependence degree will allow a better definition--in respect of the patient's will and choice--of the objectives and needed resources.