OBJECTIVE: This article presents findings from a study of the causes of homelessness among newly homeless older people in selected urban areas of the United States, England, and Australia. METHODS: Interviews were conducted in each country with > or =122 older people who had become homeless during the last 2 years. Information was also collected from the subjects' key workers about the circumstances and problems that contributed to homelessness. RESULT: Two-thirds of the subjects had never been homeless before. Antecedent causes were the accommodation was sold or needed repair, rent arrears, death of a close relative, relationship breakdown, and disputes with other tenants and neighbors. Contributory factors were physical and mental health problems, alcohol abuse, and gambling problems. DISCUSSION: Most subjects became homeless through a combination of personal problems and incapacities, welfare policy gaps, and service delivery deficiencies. Whereas there are nation-specific variations, across the three countries, the principal causes and their interactions are similar.