This chapter considers the reciprocal relationships between the Supreme Court and public opinion. Scientific research on this topic is divided into a pair of overlapping research agendas. The first considers the development of public attitudes about the Supreme Court among the American people and the consequences of those attitudes for judicial behavior and the Court’s institutional integrity. The second considers how Americans’ policy attitudes influence the behavior of justices and the decisions of the Supreme Court and how the Court’s decisions influence public opinion. We review and discuss the current state of knowledge in these areas and describe some fruitful directions for additional scholarly inquiry.