PROJECT SUMMARY/ABSTRACT. Military-connected mothers (MCM; mothers who are either service members or veterans, or spouses of a service member or veteran) experience significant trauma exposure associated with post-traumatic stress symptoms and ultimately deficits in parental functioning. Maternal trauma and its mental health and functional sequelae can have significant consequences for children, including adverse mental health outcomes. Existing evidence-based treatments (EBT) available to MCM to address trauma have not been adapted for military culture and do not fully resolve symptoms or address the bi-directional relationship between symptoms and parental functioning. To address this gap, in this R21, we propose to adapt and collect preliminary data on an innovative intervention, Parenting-STAIR (PSTAIR), which addresses trauma symptoms and parenting among MCM. PSTAIR is a novel intervention, combining two existing EBTs: Skills Training in Affective and Interpersonal Regulation Narrative Therapy (STAIR), targeting maternal emotion dysregulation and mental health symptoms, and dyadic Parent- Child Care (PC-CARE), targeting parental functioning. In an open pilot with child-welfare involved mothers, 23 session PSTAIR dramatically reduced symptoms, improved parenting skills, and prevented maltreatment. However, non-trivial treatment dropout and nonresponse consistent with other trauma- and parenting-focused EBTs were also observed; results suggest shortening and individualizing treatment may offer solutions to address dropout and nonresponse. Guided by a heuristic framework for cultural adaptation of behavioral interventions, the present study will proceed in three phases. In phase 1, we conduct qualitative interviews and focus groups with key informants including MCM to guide adaptation of PSTAIR in Phase 2. Adaptation will be guided by qualitative findings and informed by novel approaches to shorten and individualize EBTs to address dropout and nonresponse, including modular and adaptive design elements and shared decision-making between participants and clinicians. We anticipate the outcome of Phase 2 will be a 10-15 session intervention (PSTAIR-M), involving a compact version of PSTAIR in Module 1 and tailored options for Module 2, focusing on mental health (Module 2a) and parental functioning (Module 2b), implemented based on response to Module 1. Phase 3 will involve a pilot randomized controlled trial conducted in a community mental health setting, in which we will randomly assign N=120 trauma-exposed MCM who screen positive for PSTD with/without comorbid depression and one identified child (ages 2-10) to PSTAIR-M or treatment as usual. In Phase 3, we will also collect critical data on mechanisms which may account for observed effects of PSTAIR. Pilot data collection will set the stage for a future R01 in which we will conduct a full-fledged mediator-moderator clinical trial. Successful treatment with an efficient, personalized intervention...