Among the explanations for the high rates of co-occurrence between depressive symptoms and externalizing behavior is the possibility of direct causal associations between the two symptom groups. However, the mechanisms by which co-occurrence arises may not be the same across etiologically significant variables. A gender-balanced sample of 303 adolescents (ages 9-12 at the first assessment) with carefully assessed histories of maltreatment experience and 151 demographically matched nonmaltreated adolescents were assessed over the period of 1 year. Multiple-group cross-lagged panel analyses assessed the equivalence of longitudinal relations between depressive symptoms and externalizing behavior for gender/maltreatment status groups. Consistent with previous findings, the results suggest that girls, particularly maltreated girls, who exhibit early externalizing behavior are at high risk for the development of subsequent depressive symptoms. (Contains 2 figures and 3 tables.)