The authors examined differences between the verbal memory performance of older patients with major depression (MD) alone; major depression with reversible depression-related cognitive dysfunction (MD/DRCD); and primary dementia and major depression (DEM/MD). Patients were evaluated before antidepressant treatment and 6 and 15 months after treatment. Of the three groups, patients with MD alone acquired significantly more information on the California Verbal Learning Test and showed a more pronounced primacy effect. Patients with DEM/MD were more likely to commit errors of intrusion. Although older depressed patients with MD/DRCD may resemble patients with DEM/MD on some aspects of verbal memory performance, differences may be observed in the types of learning errors they commit. Diagnostic implications are discussed.