Only insufficient statistical data for epidemiologic analysis and calculations of socioeconomic costs are available in Switzerland. The total number of fractures of the proximal femur per year has nearly doubled in the 10 years from 1980 to 1990, climbing from 5500 to 9800 cases. A number of 15,000 cases is foreseen for the year 2020. In 85% of the cases the patients are older than 65 years. The global annual incidence is estimated to be 145/100,000, the partial incidence for the population of more than 65 years being 825/100,000. The mean hospitalization is 30 days. The total number of hospital days per year climbed from 200,000 to 300,000 in ten years, thus increasing the number of required beds by 50%. The mean costs for primary hospitalization is estimated to 15,000.-Swiss francs per case in 1990 and 146 Million francs globally per annum, i.e. the double of the amount in 1980. In the statistics of the National Accident Insurance Company the mean global economic costs for a fracture of the proximal femur in the active population is 57,000.-Swiss francs approximately and 72,000.-francs for patients of more than 45 years of age. Only roughly 20% of the costs are caused by medical treatment, whereas pensions, per diems and other compensations produce 80% of the costs. The mortality for patients over 65 varies from 2-7% during the primary hospitalization and rises up to 30% after 1 to 2 years after the accident. The relationship between the duration of acute hospitalization and rehabilitation is essential for planning. The evaluation of the chances for a successful rehabilitation is very important, the general medical conditions of the patients before the accident being the main determinant factor. A mean hospitalization of 3 weeks in a surgical unit and 6 to 7 weeks in a rehabilitation hospital seems to be realistic. Appropriate criteria for the selection of patients amenable to successful rehabilitation are essential. The question of the social outcome of these patients should be analyzed on a large scale nationwide study.