The purpose of this study was to evaluate the psychometric properties of the Observer Alexithymia Scale (OAS; Haviland, Warren, & Riggs, 2000) in a clinical setting. Clinical and counseling psychologists used the OAS to rate outpatients (n = 192) with various Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) diagnoses. Reliability and validity data are similar to the initial nonclinical data (n = 819): OAS scores are reliable (coefficient α = .90), and the five-factor structure-Distant, Uninsightful, Somatizing, Humorless, and Rigid-was confirmed. Moreover, the OAS does a relatively good job of differentiating clinical from nonclinical cases. The OAS is psychometrically sound, and it appears to be a useful tool for collecting and evaluating observer data on the clinically relevant, everyday expressions of alexithymia.