Objective: To study the occurrence of chronic pain in relation to different sociodemographic factors.Design and patients: The study cohort included all 1,360 new patients who, between July 1, 1988, and June 30, 1991, were referred to the multidisciplinary Pain Clinic at Malmö General Hospital, Malmö, Sweden, because of chronic, nonmalignant pain. The patients were characterized by age, sex, type of pain (nociceptive, neurogenic, psychogenic), place of residence, and ethnic background.Setting: The referred sample was from the municipality of Malmö, a city with 240,000 inhabitants in an industrialized area served by one hospital.Results: The age and sex standardized number of patients referred per 10,000 inhabitants and year varied among the different city areas from 0.35 to 1.63. High-rate areas had, in comparison to the city average, a higher migration rate, a higher proportion of single households with children, a higher percentage of people in need of social security benefits, a higher unemployment rate, and a greater percentage of people with foreign background. The age and sex distribution differed greatly among the three pain categories. Nociceptive pain was the most common category, with a striking overrepresentation of young women.Conclusion: Our results support the view that the occurrence of pain in an urban population is related to a number of sociodemographic factors. Further studies should be performed to evaluate how these factors influence incidence, medical-seeking behavior, clinical course, and rules for referral.