This research examines what strategies firms choose when their operations will have adverse impact on the natural environment and what influences that choice. It is an exploratory study in a new research area aimed at building theory from case studies. The natural environment is very prominent among social and political controversies and the condition of the environment has both direct and indirect strategic significance. Yet the management literature has for the most part neglected it. As the literatures from ecology, game theory, and other social sciences illustrate, however, the natural environment presents a paradoxical decision-making situation that all organizations face, whether aware of it or not. Because in this situation there is no "rational" criterion for what strategies "should" and at the present time no theory for what strategies "will" be chosen, this paradoxical structure constitutes a challenge to the individualistic, utility-maximizing rationality norms at the basis of strategic management. Electricity generating firms are studied because they have detrimental environmental effects and because they face technological choices with a range of environmental impact. Five U.S. utilities, two Canadian utilities, and one U.S. non-utility generator are sampled across a range of government regulation and ownership regimes. Data were collected from fourteen interviews with top executives in each firm, and from firm publications, secondary sources, and interviews with executives at two industry organizations. These were content analyzed to identify relevant corporate strategies, models of the environment, environmental attitudes, and government relations, as well as for structural and programmatic commitments to environmental issues. The findings suggest that all firms are aware of environmental issues, some much more than others. Non-utility generators aggressively adopt energy conservation and less-polluting technology to capture strong economic advantages and avoid regulatory risks. Among utilities, explicitly environmental regulation and government ownership are associated with greater environmental sophistication and greater strategic commitments, most notably voluntary collaborative, consultative relationships with regulators, environmentalists, and the public. These utilities also have strong conservation programs, which cause difficulties for those with excess capacity. Canadian firms appear vastly more sophisticated environmentally than U.S. firms.