The norm of participation means that citizens expect their democratic government to welcome their taking part in the policymaking process. As Chapter 1 showed, individuals rarely have enough clout or voice to shape public policy alone, but groups of like-minded individuals do. This chapter illustrates how American democracy encourages interest groups to form and explores the development of the American teachers’ unions as education’s dominant interest group. It explains how groups transform individual desires into group preferences by way of a bargain. In return for political clout, individuals surrender some individual identity and make the implicit promise to support or oppose a group’s political agenda. Groups like teachers’ unions lobby for equal treatment of their members by some public policy, but they strongly prefer that the public policy benefit only group members, a goal that places participation in direct conflict with the norms of equality and inclusion. For example, unions that represent government employees often favor provisions that give only members a limit on working hours, lower payments for health care premiums, or time off from work for professional development. Group-based politics may also trump self-rule and thwart attempts to inform citizens of “what works,” especially if what works is not in the interest of the members of a powerful group.