Every year about 65,000 undocumented students graduate from U.S. high schools. A major obstacle to their attending college is not being eligible for in-state tuition. Today, nine states permit it while four prohibit it. Even if the federal DREAM Act passes, state policy decisions will continue to strongly shape college opportunities for undocumented students. This situation makes the contrasting policies of Texas and Arizona—one permits in-state tuition eligibility; the other prohibits it—highly instructive. To analyze the political origins of their divergent responses, we draw on the advocacy coalition framework and policy entrepreneurship theory of policymaking.