Two models were tested examining the relationship of service members' adjustment following deployment and the impact of their postdeployment adjustment on family functioning. The study sample included 60 families participating in a longitudinal, randomized control trial of a parenting intervention adapted for military families following deployment. Baseline data collected from the participants were used for analyses. The first model focused on the association of service members' combat exposure experiences, experiential avoidance, and the interaction of combat experiences and experiential exposure with their symptoms of PTSD and depression, and with their alcohol use. Results indicated that both experiential avoidance and combat exposure were associated with PTSD symptoms, and only experiential avoidance was associated with depressive symptoms. The second model examined the relationship of service members' postdeployment adjustment to their behavior during family interaction. Three behavior patterns of service members were assessed and analyzed: (a) reactivity-coercion, (b) withdrawal-avoidance, and (c) positive engagement. Coding and analyses of service members' behavior during family interaction confirmed these three patterns, and a fourth unexpected behavior pattern emerged: challenge positive engagement, characterized by efforts to soothe or otherwise minimize distressing and emotion-laden family interactions. Results of the second model indicated that experiential avoidance was reliably related to service members' observed challenge positive engagement behavior pattern, but not to any of the other three behavior patterns during family interaction. This suggests the novel challenge positive engagement behavior interaction pattern may serve a dual function, both as a constructive interpersonal response to reduce other family members' distress and as an intrapersonal means of minimizing the service members' own distress in response to that of other family members.