PROJECT SUMMARY/ABSTRACT An estimated 250 million or 43% of children under age 5 years are failing to reach their developmental potential in low- and middle-income countries (LMICs). Parenting interventions, or programs that primarily focus on enhancing the quality of parent-child relationships, have shown effectiveness for improving early child development (ECD) outcomes. However, the majority of evidence-based parenting interventions to date have been designed for, delivered to, and evaluated among mothers and have excluded fathers. Observational studies in high-income countries have supported that fathers’ parenting and couple’s relationships are unique dimensions of fatherhood that independently and interactively shape the influence of fathers on young children’s development. While there is increasing cross-cultural evidence to support these dimensions of fatherhood in LMICs, very little is known about how to engage fathers and address these important aspects of fatherhood through parenting interventions in sub-Saharan Africa. The goal of this K99/R00 Pathway to Independence Award is to prepare the candidate for a successful transition to an independent intervention scientist with an international research focus on promoting ECD outcomes by supporting fathers through community-based interventions in LMICs. The goal will be accomplished through training during the mentored phase (K99) to broaden the candidate’s knowledge and skills in three critical areas: 1) multidisciplinary and cross-cultural training in ECD, fatherhood, and family science, 2) latent profile analysis, and 3) intervention development and evaluation science. The candidate has assembled an outstanding mentorship team with complementary expertise in theoretical, substantive, and methodological skills. These training objectives will be achieved through a holistic approach that includes regular mentorship meetings, coursework, trainings, conferences, and field- based research experience in Tanzania. The specific research aims of the K99 phase are to: 1) characterize profiles of fatherhood based on measures of fathers’ parenting and couple’s relationships, and determine their associations with later ECD outcomes, and 2) integrate and adapt a multicomponent parenting intervention that supports fathers’ roles as parents and partners in the Tanzanian cultural context. The mentored training and research findings from the K99 phase will enable the candidate to accomplish the final research aim of the independent phase (R00) that is: 3) to conduct a mixed-methods pilot trial of the newly adapted fatherhood intervention for improving paternal outcomes. This proposal will generate the first evidence-based, multicomponent parenting intervention that is designed from the outset for fathers in the Tanzanian cultural context. The pilot trial results will be used to determine program feasibility and acceptability and initial intervention efficacy on paternal outcomes to support a subsequent R0...