The system the United States has, structurally (separate institutions sharing powers) and by culture and extra constitutional institutions (weak parties, fragmented power in the Congress, and so on), provides multiple masters of the large bureaucracy that has developed. When public opinion or interest groups demand it, or intra- or interinstitutional rivalries inspire it, or even when the spirit is there for idiosyncratic reasons, congressional actors in the U.S. system are unusually well positioned to respond by playing an active role in relation to the bureaucracy through various means, including oversight of policy and administration. The main reason for an excellent cohesiveness is the excellent of the Congressional House.
In its most elemental form, Congress consists of its members (and their supporting personnel and resources) acting within a more or less precisely defined (by rules and customs) institutional setting to achieve specific goals or end results. These products, in a very real sense, grow out of the ideas, values, and beliefs of the senators and representatives who seek to realize them within the constraints that the structures and processes of the legislature impose. In other words, to achieve whatever they seek from congressional service, individual members of Congress must act within an institutional setting that will facilitate some and hinder other activities. That setting, moreover, includes not only features of Congress itself (e.g., the existence of two chambers, House and Senate, and committees, political parties, and rules of procedure within each) but also the relationships of lawmakers with numerous individuals and institutions (e.g., executives, lobbyists, and citizens) outside the legislature. In short, to understand what Congress does, and why, we need to know about its members (who they are and what they have experienced); its organizational structure, formal and informal; and its contacts with numerous nonmembers..................
