Internalizing and externalizing problems commonly co-occur with adolescent post-traumatic stress and grief reactions. However, little is known about whether these co-occurring symptoms moderate adolescents’ response to sequenced components of trauma- and grief-focused interventions. Forty-four middle school students (aged 12-14) rated their self-identified Top Problem during a 17-week flexibly tailored course of Trauma and Grief Component Therapy for Adolescents (TGCTA), a group-based treatment for traumatized and bereaved youth. Baseline internalizing and externalizing symptoms were examined as potential moderators of adolescents’ response to skills-building (Module I), narrative-sharing (Modules II and III), and developmental progression (Module IV) phases of intervention. Piecewise analyses of change during the three treatment phases indicated that adolescents with more internalizing symptoms showed significantly less improvement during the skills-building phase and significantly more improvement during the narrative construction phase. Findings provide preliminary evidence that: (a) traumatized and bereaved adolescents show different trajectories of response to different TGCTA components as a function of internalizing versus externalizing baseline symptoms and (b) assessing self-nominated problems and broad-spectrum internalizing and externalizing symptoms can guide trauma- and bereavement-informed treatment planning and monitoring.