The objective of this program is to develop a dedicated, accelerator-based 13N-ammonia delivery system for positron emission tomography (PET). 13N- ammonia PET scans can accurately measure myocardial blood flow and have been shown to be valuable tools in diagnosing coronary artery disease. 13N-ammonia can also be utilized to measure blood flow in other parts of the body, including the liver, kidney, brain and malignant tumors. The proposed generator will utilize a very low energy Coaxial Cascade Accelerator (CCA) developed at SRL to produce 13N via the 12C(d,n)13N nuclear reaction. The fully shielded acceleratory and 13N-ammonia production system will be housed in a 1.8 m x 1 m x 1.2 m enclosure and will be fully automated with easily operated push-botton controls. The estimated cost of the 13N-ammonia delivery system is comparable to that of a one of a one year supply of 82 Rb, another commonly used blood flow agent.