PROJECT SUMMARY/ABSTRACT Global health agencies have identified migration as a common and key determinant of health and well-being, with women disproportionately vulnerable to higher HIV risk and poorer health service access and utilization. African American women are among the key populations hardest hit by the HIV epidemic in the U.S. and have sustained markedly higher participation in migration compared to White populations for two decades due to gendered and racialized trends. Data illuminating complex HIV service linkage barriers among migrant women advocate for leveraging social networks as innovative avenues for HIV testing and treatment interventions. This approach is particularly relevant given migrants' reliance on networks to relocate and the robust influence of networks on social support and health behaviors. While network-based strategies have proven effective in promoting HIV service linkage among diverse groups, they are currently untested, untailored, and unsuitable to meet the culturally specific needs of African American migrant women. This K01 Mentored Research Scientist Development application is among the first to examine the influence of migration-driven social support network dynamics and characteristics on HIV testing and treatment (Aim 1) among African American women migrants, aiming to develop (Aim 2), implement, and evaluate (Aim 3) a social network-based HIV service intervention. The study site, Atlanta, GA, is a southern urban center with a disproportionately high burden of HIV incidence and prevalence among African American women. It is also the most populous destination city for over 2 million African American New Great Migration migrants. African American women, who bear the highest burden of HIV risk, prevention, and treatment inequities among all other groups of women in the U.S., constitute the majority of New Great Migration migrants. This K01 will provide necessary training in (1) advanced longitudinal social network data analyses, (2) mixed methods, (3) social network intervention design, and (4) testing and evaluation. These skills are crucial for achieving my long-term goal of becoming an independent scientific pioneer who uses interdisciplinary and community-led methods to develop high-impact network-based health interventions for African American women. The career development and training essential to launching my independence will be led by a multidisciplinary and internationally recognized team of experts in mixed- methods HIV research and interventions with migrants (Primary mentor: Dr. Carol Camlin), longitudinal dynamic social network research methods and analysis in public health research (Co-mentor: Dr. Jim Moody), advanced statistical analyses using multilevel modeling (Co-mentor: Dr. Tor Neilands), and HIV intervention design, implementation, and evaluation (Co-mentor: Dr. Jae Sevelius, Advisor: Dr. Sophia Hussen).