We examined beliefs about depression in patients and their partners and explored the impact of beliefs on perceptions of marital functioning, level of distress and caregiving in partners, and clinical outcome of major depression. Fifteen patients meeting criteria for major depressive disorder and their co-habiting spouses were interviewed at baseline using the Reasons for Depression Questionnaire (Addis, Truax and Jacobson, 1995) and measures of symptom severity, distress, caregiver consequences and marital satisfaction. Outcome was assessed at 6 months. Identifying biological reasons for depression was significantly associated with patient severity of depression and with caregiver burden. Caregiver distress was significantly associated with endorsement of interpersonal reasons for depression. Concordance in reason giving between patients and partners was significantly associated with a good outcome. This is the first study to show that beliefs about depression held by patients and their partners may have an impact on the clinical outcome of major depression.