During the 14‐month period from May 2002 through June 2003, approximately 10% of U.S. supermarkets began to offer fresh irradiated ground beef under the stores' own labels. Using a survey of supermarket store managers from this period, the authors investigate the factors that influenced stores' adoption of irradiated ground beef. Results from the adoption model show that factors associated with competition, merchandising philosophy, and structure in the food retailing industry play a strong role in the decision. Among other results, it was found that variables relating to a competitor's adoption status and proximity can increase the likelihood of a store's adoption.