Clarity doctrines are a pervasive feature of legal practice. But there is a fundamental lack of clarity regarding the meaning of legal clarity itself, as critics have pointed out. This article explores the nature of legal clarity as well as its proper form. In short, the meaning of legal clarity in any given doctrinal context should turn on the purposes of the relevant doctrine. And the reasons for caring about clarity generally have to do with either (i) the deciding court’s certainty about the right answer or (ii) the predictability that other interpreters (apart from the deciding court) would converge on a given answer. Each of these two sorts of reasons gives rise to a model form of legal clarity with its own strengths and difficulties. More generally, debates about what type and degree of clarity to require often reflect implicit disagreements about the relevant clarity doctrine’s goals. So by challenging a doctrine’s accepted purposes, reformers can justify changes in clarity doctrines. To show as much, this article discusses a series of clarity doctrines and illuminates several underappreciated avenues for reform, particularly as to federal habeas corpus, Chevron, qualified immunity, constitutional avoidance, and the rule of lenity. Finally, this article acknowledges, but also discusses ways of mitigating, several anxieties about clarity doctrines, including worries that major clarity doctrines are too pluralistic, malleable, or awkward.