Disputes involving the boundaries of state versus federal power make up a substantial portion of the U.S. Supreme Court’s docket and have undergone extensive analysis. Yet, the conventional wisdom regarding the justices’ choices in these cases is that they are highly inconsistent. I argue that this is primarily a function of the failure of scholars to develop a comprehensive model of the justices’ federalism decision making. To remedy this, I introduce an integrated model of the individual justices’ choices in these cases, which is then subjected to empirical testing in the Rehnquist Court era (1986^2004). I explore a host of determinants of the justices’decision making, including attitudinal, institutional, legal, and personal attributes, as well as the role of organized interests in the Court. The findings reveal that the choices justices make in these cases are not as discordant as most commentators suggest. Rather, they are relatively predictable through the application of an integrated model of judicial choice. Each term, U.S. Supreme Court justices adjudicate disputes implicating the limits of federal versus state power. Through these federalism decisions, the justices are charged with determining the proper balance between the authority of states to operate as sovereign entities, free from federal interference, and the expansiveness of the federal government’s reach under the Constitution. The importance of this debate is perhaps no more evident than in scholarly analyses of the Rehnquist Court’s so-called ‘‘federalism revolution,’’ in which the justices, under the leadership of Chief Justice Rehnquist, are argued to have reinvigorated the concept of taking states’ rights seriously to a level that had not been witnessed since before the New Deal (Chen 2003; Greenhouse 2001; Pickerill and Clayton 2004). In so doing, the Rehnquist Court appeared to breathe new life into conspicuously long-forgotten constitutional provisions involving federalism as it struck down federal laws involving a wide range of social policies, including the regulation of firearms on school property (United States v. Lopez [1995]), violence against women (United States v. Morrison [2000]), and the free exercise of religion