This K01 award resubmission outlines an intensive five-year research career development program focused on multilevel behavioral intervention and dissemination and implementation science research to increase and sustain uptake of the human papillomavirus (HPV) vaccine. Supporting the candidate's career and research goals is a mentoring team comprised of experts in behavioral intervention research, advanced biostatistics methods, and dissemination and implementation science as well as a clinical expert panel. Completion of the candidate's training plan and research study will provide the candidate with the experience, skills, knowledge, mentoring and pilot data needed to become a leading independent investigator in developing, implementing and evaluating multilevel behavioral interventions to reduce the burden of cancer in racial/ethnic minority groups, starting with increasing HPV vaccination rates. The HPV vaccine is a major public health breakthrough and is the optimal primary prevention strategy against HPV-associated cancers. Widespread use of the HPV vaccine is expected to reduce the cancer burden across all racial/ethnic group, as populations of color are disproportionately affected by HPV- associated cancers. Despite CDC recommendations and the public health implications of full vaccination coverage, HPV vaccine uptake among adolescents remains well below the Healthy People 2030 goal of 80%. The National Immunization Survey reported that in 2019, only 54.2% of U.S. adolescents aged 13-17 were up to date with the series. Preliminary data and a review of the literature suggest multilevel interventions that address at least two levels influence show promise in increasing HPV vaccine uptake. The objective of this proposal is to develop, implement and evaluate a multilevel (parent, primary care team, and clinic) intervention aimed at raising adolescent HPV vaccination rates to the Healthy People 2030 goal of 80% for boys and girls using a parallel group cluster randomized trial design. This study will assess the effectiveness of the multilevel intervention on increasing the rates of HPV vaccination among patients aged 9-17 of a primary care network and will identify barriers and facilitators for broad dissemination and implementation. This will be accomplished through the following aims: 1) Refine and finalize a parent, primary care team and clinic ML intervention to increase uptake and completion of the HPV vaccine series among adolescent patients of a primary care network; and 2) Conduct and evaluate the effectiveness and sustainability of the ML intervention. The proposed research is significant because it will contribute to the emerging field of HPV vaccination multilevel intervention research and addresses the need for more scientifically rigorous, evidence-based interventions that can be disseminated and implemented on a large scale. Successful adoption of widespread HPV vaccine coverage programs will reduce racial/ethnic disparities in ...