Abstract: Experiments of Living Constitutionalism urges that the Constitution should be interpreted so as to allow both individuals and groups to experiment with different ways of thinking, whether we are speaking of religious practices, family arrangements, political associations, civi associations, child-rearing, schooling, romance, or work. Experiments of Living Constitutionalism prizes diversity and plurality; it gives pride of place to freedom of speech, freedom of association, and free exercise of religion; it cherishes federalism; it opposes authoritarianism in all its forms. While Experiments of Living Constitutionalism has considerable appeal, my purpose in naming it is not to defend it, but to contrast it to Common Good Constitutionalism, with the aim of specifying the criteria on which one might embrace or defend any approach to constitutional law. My central conclusion is that we cannot know whether to accept or reject Experiments of Living Constitutionalism, Common Good Constitutionalism, democracy-reinforcing approaches, moral readings, originalism, or any other proposed approach without a concrete sense of what it entails--of what kind of constitutional order it would likely bring about or produce. No approach to constitutional interpretation can be evaluated without asking how it fits with the evaluator's "fixed points," which operate at multiple levels of generality. The search for reflective equilibrium is essential in deciding whether to accept a theory of constitutional interpretation.