Building C at TRPRC has not been significantly renovated in 25 years. Funds are requested to modify the west wing of Building C to help meet the needs of expanding research program. The proposed modifications will result in the creation of five large BSL2 animal holding rooms and completely change heating, ventilation, and air-conditioning (HVAC) system in that building. The renovations will also provide a safer work environment for animal care workers and modernized walls, floors. drainage, HVAC, and environmental monitoring systems. Rolling rack caging systems will be used to reduce worker injury and facilitate cage sanitation. The proposed changes in conjunction with other facilities being built by the Center will create space for 200 additional BSL2 cages for our research program. Several research projects will be supported by the increased holding capacity of the building. Design and materials will ensure continued AAALAC accreditation in the future.