Main features of hospital stay in Chile are analyzed with special regard to incidence, geographic, sex and age variations, main causes and trends observed in the last decades. The annual admission rate in 1989 was 107 per 1000, twice the overall Latin American rate. Wide variations are observed among geographical areas, with relatively low use of hospital beds in the capital city of Santiago. Hospital needs differ for men and women and according to age, being greater for infants, older people and women of childbearing age. Near two thirds of the needs are related to pregnancy. Admissions for traumatic, digestive, respiratory, urinary and gynecological problems are also frequent Accidents are the main cause for hospital admission among males, while tumor is foremost among women. During the last 30 years the hospitalization rate has remained stable while the cass fatality rate has decreased. Different factors influencing the frequency and features of hospital stay are discussed.