In 1988, the DuPont Co. is abruptly confronted with solid scientific evidence that chlorofluorocarbons are destroying the earth's ozone shield. DuPont, with its Freon brand product line serving markets for foam insulation, electronics solvents, and especially refrigeration, was the world's leading producer of these chemicals. Although no substitutes were currently commercially available, or even proven, DuPont had to decide what to do. The purpose of the case is to examine how changing science and environmental problems affect competitive conditions and corporate strategy. In particular, the case examines the criteria by which companies formulate policy.