The cost and prevalence of chronic work-related musculoskeletal pain disability in industrialized countries are extremely high. Although unrecognized psychiatric disorders have been found to interfere with the successful rehabilitation of these disability patients, few data are currently available regarding the psychiatric characteristics of patients claiming work-related injuries that result in chronic disability. To investigate this issue, a consecutive group of patients with work-related chronic musculoskeletal pain disability (n = 1595), who started a prescribed course of tertiary rehabilitation, were evaluated. Psychiatric disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders. Results revealed that overall prevalences of psychiatric disorders were significantly elevated in these patients compared with base rates in the general population. A majority (64%) of patients were diagnosed with at least one current disorder, compared with only 15% of the general population. However, prevalences of psychiatric disorders were elevated in patients only after the work-related disability. Such findings suggest that clinicians treating these patients must be aware of the high prevalence of psychiatric disorders and be prepared to use mental health professionals to assist in identifying and stabilizing these patients. Failure to follow a biopsychosocial approach to treatment will likely contribute to prolonged pain disability in a substantial number of these patients.