Sometimes our intentions and beliefs exhibit a structure that proves us to be irrational. The Normativity of Rationality is concerned with the question of whether we ought to avoid such irrationality. Benjamin Kiesewetter defends the normativity of rationality by presenting a new solution to the problems that arise from the common assumption that we ought to be rational. The argument touches upon many other topics in the theory of normativity, such as the form and the content of rational requirements, the preconditions of criticism, and the function of reasons in deliberation and advice. Drawing on an extensive and careful assessment of the problems discussed in the literature, Kiesewetter provides a detailed defence of a reason-response conception of rationality, a novel, evidence-relative account of reasons, and an explanation of structural irrationality in terms of these accounts.