Since 2000, approximately $50 million per year has been spent to control infestations of the Glassy-Winged Sharpshooter (GWSS), an insect that spreads Pierce’s Disease (PD). This amount includes the costs of state and federal efforts to monitor and control the GWSS, research on PD/GWSS, and compliance with the PD Control Program. Using a simulation model of the market for California wine grapes, we estimate that under the current program, PD costs winegrape growers and consumers $92 million annually. If the program ended and the GWSS became widespread throughout California, the annual cost borne by growers and consumers would increase by an estimated $185 million.