Abstract – Core A: Husbandry and Management Core Indian-origin rhesus macaques are a premier model for AIDS research, but current research demand far exceeds supply. This has been exasperated by the COVID-19 pandemic, where rhesus have proved again to be a vital model for the development of vaccines and therapeutics. This project will help alleviate this shortage by the production of Indian-origin, specific pathogen free (SPF) rhesus macaques prioritized for AIDS-related research that are well characterized by genotype and phenotype. Using established methods, we will utilize genomic, behavioral, and demographic data to optimally compose and monitor rhesus breeding groups. We will also increase the size of our rhesus colony via an increase in the number of female breeders, institutionally supported acquisition of additional macaques for breeding and/or research purposes, and occupation of newly renovated areas for rhesus production. We will continue to provide rhesus for AIDS-related and other approved NIH research. Towards this end, we will focus on Specific Aim 1: maximize the genetic diversity and production efficiency of the SNPRC SPF breeding colony by genetically and reproductively managing it in concert with the MHC Genetic Typing Core and Specific Aim 2: grow the U42 Colony towards an approximate steady state of 1000 animals, at which time approximately 150 rhesus macaques will be made available for AIDS research annually. The rhesus macaque colony supported by this U42 will continue to serve as a critical national resource for AIDS investigators.