This article examines the prevalence and causes of homelessness among older people. It reviews the histories of a sample of older people in Britain who slept on the streets and stayed in temporary hostels. Some had become homeless for the first time in old age, having been married and worked for many years. Others had spent most of their adult lives in hostels or on the streets. Different events and states triggered and contributed to homelessness at various stages of the life course. Although homelessness generally is associated with shortages of low-cost rented housing, unemployment, and poverty, among our informants personal and psychosocial factors had a dominant role. (Authors)