During the past two decades Congress has enacted numerous pieces of legislation for the prevention of environmentally-provoked disease and for reducing ecological risk. The transmutation of these policies into action has been plagued by problems of delay, interagency disagreement, and inadequate resources. As the executive and legislative branches of the federal government try within the next four years to settle and move beyond a number of large environmental health and ecological issues, they must be constantly alerted to the limitations inherent in the implementation phase of the policy process, and not raise public expectations beyond what is realistically achievable in terms of policy impact (i.e. changes in the environment that are associated with measures of government activities).