Substantial rates of comorbid anxiety disorders have been found using structured research diagnostic interviews in depressed outpatients. Comorbid anxiety disorders is underrecognized in routine clinical settings, in which clinicians usually use unstructured diagnostic interviews. Recognition of comorbid conditions such as anxiety disorders in patients seeking treatment for depression is clinically important because the presence of these disorders might influence selection of treatment options or predict the chronicity of the depression. A reliable and valid self-report screening questionnaire, such as the Psychiatric Diagnostic Screening Questionnaire (PDSQ), would potentially enhance usual clinical practice as a useful diagnostic aid.