The authors evaluated personality disorder symptoms as predictors of change in global functioning and quality of life among elderly depressed patients. Treated elderly patients (N=40) who no longer met RDC criteria for major depression were assessed for personality disorders, depression, global functioning, and quality of life after treatment of the acute episode and at 1-year follow-up. In interaction with persisting or recurrent depression, Cluster B personality disorder symptoms contributed to declines in global functioning and quality of life over a 1-year period. Personality disorder symptoms in elderly patients appear to operate as co-factors that amplify or exacerbate the impact of residual depression on long-term functioning and quality of life.