In this longitudinal study, we followed a large sample of first-time parents (both partners) across the first 2 years of the transition to parenthood. Guided by attachment theory (Bowlby, 1969), we tested several predictions about how attachment anxiety and avoidance are related to the incidence, maintenance, increase, and decline of depressive symptoms in both sexes across the first 2 years of the transition. We found that (a) the association between attachment anxiety and depressive symptoms was moderated by factors related to the marital and/or romantic relationship; (b) the association between avoidance and depressive symptoms was moderated by factors related to family responsibilities; (c) styles of caregiving provided by romantic partners affected depressive symptoms differently among anxious and avoidant persons; and (d) in certain predictable situations, depressive symptoms persisted at higher levels or increased to higher levels in anxious or avoidant persons across the 2-year transition period. Important implications of these results are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)