This paper reports the results of two studies in a nonclinical (n=105) and primary care outpatient sample (n=110), in which Depressive Personality Disorder (DPD), Dysthymia, and depression were assessed for their distinctive relationship with perfectionism. Results from both studies found that self-reported DPD, Dysthymia, and depressive symptoms were all intercorrelated, and that DPD, Dysthymia, and depressive symptoms were correlated with three dimensions of perfectionism-Concern over Mistakes, Doubts about Actions, and Parental Criticism. In the nonclinical sample, variance in measures of DPD was predicted by measures of perfectionism after controlling for depression and Dysthymia symptoms. A similar pattern of findings was observed in the primary care sample. This relationship with perfectionism did not occur when Dysthymia or depressive symptoms were predicted. Nevertheless, much of the variance in measures of DPD, Dysthymia, and depressive symptoms is associated with each other and not perfectionism. It is concluded that a common factor or set of factors underlies these disorders, but that DPD may be more strongly related to perfectionism than Dysthymia and depression. As a common factor(s) is identified, measures of DPD and Dysthymia may be refined, thereby increasing the discriminant validity of their measures.