I defend a methodology for theorizing about happiness. I reject three methods: conceptual analysis; scientific naturalism; and the “pure normative adequacy” approach, where the best conception of happiness is the one that best fills a role in moral theory. The concept of happiness is a folk notion employed by laypersons who have various practical interests in the matter, and theories of happiness should respect this fact. I identify four such interests in broad terms and then argue for a set of desiderata that theories of happiness ought to satisfy. The theory of happiness falls with the province of ethics. It should, however, be viewed as autonomous and not merely secondary to moral theory.