The present study aims to validate the Spanish version of the Hospital Anxiety and Depression Scale (HADS) and to determine the use of this tool for screening mood and anxiety disorders. Psychometric properties of the HADS were assessed in different groups of general medical outpatients attending the Hospital Clínic in Barcelona (N=385), and psychiatric diagnoses were made using DSM-IV criteria. A two-factor solution corresponding to the original two subscales of the HADS was found. The Spanish version of the HADS had good internal consistency and external validity, with favorable sensitivity and specificity in identifying cases of psychiatric disorder as defined by the Structured Clinical Interview for DSM-IV (SCID-I). The psychometric properties of the HADS and its brevity make it useful for screening for psychiatric disorders in the medically ill.