This chapter examines the organized religious groups that work to affect politics and policy. It traces their roots, explores their growth, and charts their stands on front-burner political issues. The chapter suggests that five factors contribute to success: amenable traditions and theological beliefs; internal strength and unity; strategic location; constraints and opposition from other groups; and favorable "spirit of the times". The kinds of outside pressure brought by interest groups vary tremendously by group and context. Mass mobilization, a technique commonly used by conservative Protestant organizations, represents one approach. A treatment of outside pressure and inside influence would be incomplete without a discussion of the cyber revolution, which has transformed mobilization and woven it deeply into the policy-making process. At the heart of the legislative process—whether in Congress or in statehouses—is consensus-building. The story of the Mennonite Central Committee illustrates how the actions of the federal government have spurred the growth of church lobbies.