Project Summary The common marmoset (Callithrix jacchus) has experienced unprecedented growth in research across the United States and is rapidly emerging as a likely keystone biomedical model system in the next chapter of scientific discovery. Over the past decade, the number of marmoset laboratories in the US has quadrupled. There are now over 40 Principal Investigators who use marmoset as the model system in their research. Neuroscience is the primary engine driving marmoset research today, as nearly three quarters of marmoset researchers in the US use this model species to examine molecular, systems or cognitive functions in normal and diseased brains. Although these grassroots have been successfully forged new paths of scientific inquiry using marmosets in the U.S., critical bottlenecks have emerged that threaten to thwart the continued growth of this emerging model system. We propose to establish a Bicoastal Marmoset Breeding center, with two breeding colonies, one on the East Coast at Johns Hopkins University (JHU) and the other on the West Coast at University of California at San Diego (UCSD). The Center aims to produce a large number of marmosets to supply the marmoset research community in the U.S. Because of the non-availability of air transport of NHP in U.S. and prohibitively expensive ground transportation of NHP between the east and west coast, these two breeding colonies are strategically located to support the marmoset community in regions near each colony. We believe such a center is needed to address the national shortage of marmosets in order for the marmoset model to realize its full potential as a keystone species in the next chapter of neuroscience that serves to accelerate the rate of discovery and better understand human neurological disease.