Approximately one third of elderly persons over the age of 65 who live in the community fall each year. About 5% of falls result in a fracture, and 5 to 10% of them result in other serious injuries requiring medical care. Even in the absence of serious physical injury, falls may have severe psychological consequences leading to an accelerated decline in functional capacities. Several epidemiological studies have identified the main intrinsic risk factors for fall. These include advanced age, female sex, impaired balance, gait abnormalities, reduced muscular strength, cognitive deficiencies, impaired visual acuity and use of sedative-hypnotic medications. The results of recent epidemiological studies comparing falls with serious physical injuries to falls without injuries suggest that, besides bone mass, the speed and effectiveness of protective reflexes may greatly influence the risk of trauma after a fall. Contrary to what may be believed, the frequency of falls and fall-related trauma is also high in active and healthy subjects. However, the cause of falls are clearly different for persons of varying age, health status and level of mobility. Several authors have tried to define different types of falls according to the predominance of intrinsic or extrinsic factors in fall aetiology. This approach may allow to identify different risk factors or combinations of risk factors according to the type of falls or to the characteristics of fallers.