To assess the long-term impact of trauma and confinement on the functional health and mental health status of Cambodian displaced persons living on the Thailand-Cambodia border. Household survey of 993 adults randomly selected from household rosters. Household sample selection by multistage area probability sample. Site 2, the largest Cambodian displaced-persons camp on the Thailand-Cambodia border. Adults 18 years of age and older selected at random within households; 98% of eligible persons selected agreed to participate. From 1975 through 1979 (Khmer Rouge regime), more than 85% reported lack of food, water, shelter, and medical care, brainwashing, and forced labor; 54% reported murder of a family member or friend; 36% reported torture; 18% reported head injury; and 17% reported rape or sexual abuse. During the refugee period between 1980 and 1990, 56% reported lack of food or water, 44% reported lack of shelter, 28% reported lack of medical care, 24% reported brainwashing, and 8% reported torture. Since 1980, reports of murder of a family member, head injury, and rape/sexual abuse have decreased to 5%. Reports of experiencing combat situations and shelling attacks have remained consistent between the two time periods, approximately 44% and 30%, respectively. From 1989 to 1990, 25% reported experiencing lack of food or water, and 5% to 10% reported serious injury, combat, and shelling conditions. More than 80% said they were in fair or poor health, felt depressed, and had a number of somatic complaints despite good access to medical services. Fifty-five percent and 15% had symptom scores that correlate with Western criteria for depression and posttraumatic stress disorder, respectively. Fifteen percent to 20% reported health impairments limiting activity, and moderate or severe bodily pain. Despite reported high levels of trauma and symptoms, social and work functioning were well preserved in the majority of respondents. Reports of extensive trauma, poor health status, and depressive symptoms of this population are of concern in predicting future morbidity and mortality. The health and mental health needs of Cambodian displaced persons and their impact on social and economic behavior should be addressed now that the Cambodians have been repatriated.