Humans have an intrinsic need to form and maintain interpersonal relationships. Therefore, difficulties and problems in interpersonal functioning are likely to influence and be influenced by mental health outcomes such as depression. In this chapter, key theories and empirical findings regarding interpersonal perspectives on depression are reviewed. Specifically, the review focuses on problematic interpersonal characteristics and processes (i.e., excessive reassurance seeking and rejection, circumplex models of problematic interpersonal behaviors, interpersonal stress and stress generation, anxious and avoidant attachment, social skills deficits) and poor quality interpersonal relationships (i.e., marriage and intimate relationships, family relationships) that are associated with the onset, severity, and course of depression. Implications of these interpersonal perspectives for the treatment of depression are also reviewed, and suggestions for future research are advanced.