This study examined maladaptive perfectionism (concern over mistakes, doubts about one's ability to accomplish tasks, and failure to meet high standards) as both a mediator and a moderator between adult attachment (anxiety and avoidance) and depressive mood (depression and hopelessness). Survey data were collected from 310 undergraduates and analyzed using structural equation modeling (SEM) methods. Results indicated that maladaptive perfectionism partially mediated the relationship between attachment anxiety and depressive mood and fully mediated the relationship between attachment avoidance and depressive mood. Bootstrap methods were used to assess the magnitude of the indirect effects. Significant moderator effects were also found with SEM methods. The association between attachment anxiety and depressive mood was stronger as perfectionism increased. Perfectionism was not a significant moderator for attachment avoidance and depressive mood.