This is an Essay about "the how" of constitutional interpretation. Much attention has been devoted to the question of how the Constitution is interpreted in courts. Rather little attention has been devoted to the question of how the Constitution is interpreted elsewhere in the government. The Constitution tells us that Congress, the President, and state legislators and courts must adhere to its terms, but it does not tell us how much interpretive power each actor should have, nor does it prescribe rules for each actor to use when interpreting the text. The author argues that constitutional interpretation by Congress is, and should be, quite different from constitutional interpretation by courts. In so doing, he combines insights from political scientists about the ways Congress operates with insights from constitutionalists who fear open-ended interpretation.