Quality of life is used to assess the overall impact of medical treatments from the patient's perspective. Because depression affects a person's ability to function at work and at home, the evaluation of various treatments must include an assessment of patients' physical, social and psychological status. This paper classifies and evaluates a variety of widely used health-related quality-of-life questionnaires that have potential value as outcome measures in the treatment of depression. The paper also outlines how these measures have been beneficial in the assessment of depressed patients. They reveal differences between patients with depression and control groups, are sensitive to change in status during treatment, have predictive value for outcome measures and provide additional information about timelines for improvement in psychosocial functioning, which may occur at a different rate than changes in other depressive symptoms. Despite the limitations of these questionnaires, they provide an important additional dimension to the evaluation of treatment with antidepressant medications.