Robert A. Dahl's Who Governs? is a classic pluralist study which has had an important influence on American social science since the early sixties. Who Really Rules? provides a categorical challenge—empirical, methodological, and theoretical—to Dahl's work. Empirically, Domhoff's restudy of New Haven shows through newly discovered documents that Dahl was wrong about the pluralism of New Haven's power structure. He also presents the most systematic statement of power structure methodology yet made, a statement that contradicts Dahl's methodological claims which have been the prevailing wisdom in American social science for over fifteen years. Finally, Domhoff outlines the national policy planning network through which the big business ruling class dominates urban government.