The Nonhuman Primate (NHP) Core is a multicenter Core structured to provide the Pacific Northwest Regional Center of Excellence (PNWRCE) with resources for purpose-bred animals and unique facilities and specialized investigative and technical expertise for infectious disease research that is best conducted using NHPs. The Core's performance sites include the Oregon and Washington National Primate Research Centers (ONPRC Beaverton, OR, and WaNPRC, Seattle, WA), and the Integrated Research Facility (IRF) on the Rocky Mountain Laboratories (RML) campus, Hamilton, MT. Nonhuman primates are unique, long-lived species that share many physiologic similarities with humans. These similarities include body composition, maturation, reproduction, metabolism and close genetic relatedness. Of NHPs available for research, Old World monkey species have the closest evolutionary relationship to humans and they are essential surrogates for biomedical research focused on major human diseases that lack suitable alternative animal models. The organization and function of the NHP immune system closely resembles that of humans and their contribution to understanding the complex interrelationships of the different components of the immune system in the defense against infectious agents is particularly notable. Nonhuman primates have long been recognized for their value as comparative models for human vaccine development, efficacy testing and safety evaluation, and for the investigation of fundamental questions in basic immunology. Many of these models have demonstrated merit for pathogenesis research and vaccine development to contain emerging and re-emerging infectious diseases, H5N1 and 1918 influenza (1-3), Ebola and Marburg viruses (4), monkey pox virus (5, 6), West Nile virus (7, 8), Junin virus (9), yellow fever virus and Dengue fever virus (10, 11). Their research value notwithstanding, NHPs are complex, higher order species that require specialized expertise, infrastructure and staff in a research setting.