In the past century the American political system has changed in dramatic ways. A new national state has been created, and a substantial part of the nation's goods and services has been entrusted to its care. New administrative agencies allocate most of those resources, working in tandem with a multitude of private and other public organizations. Complex webs of fiscal interaction tie state and local governments—themselves greatly enlarged—to the nation state. All these public bodies are surrounded by and closely allied with formidable interest groups, with political action committees, with business corporations and foundations, and with various professional organizations. Swirling about this great governmental mass in recent years are the consultants, lawyers, and technicians who slip in and out of the public sector as administrations change or their careers dictate; these policy professionals, wherever they land, make use of their special knowledge and contacts in particular areas of public activity.