The direction and extent of weight change during two separate episodes of severe, unipolar depression were assessed in 53 (unmedicated) outpatients in the Pittsburgh (Pa) study of maintenance therapy of depression. There was a high concordance (45 of 53 patients) of direction of self-reported weight change during the two episodes. Twenty-three patients lost weight during both episodes, 17 gained weight, and 5 showed no change. The extent of weight change between the two episodes was highly correlated. Self-reported weight change corresponded closely to measured weight changes in a large sample of the study population. Changes in appetite paralleled those in body weight. Duration of the episode and body mass index were related to the weight change, but two features of depression with which weight loss in depression has been associated (the endogenous character of the depression and it severity) were not. Direction and extent of weight change in unipolar depression appear to be stable patient characteristics across episodes and are thus potential markers for subtypes of depression. This stability of weight change is in sharp contrast to the lack of stability of the endogenous subtype in consecutive episodes of major depression.