A reason for action is a premise of practical reasoning. When someone acts for a reason, doing φ on the ground that p, she reasons from that premise, though her reasoning may not be explicit or calculative or conscious, and though it may not be sound. We are here describing what some call "explanatory" or "motivating" reasons.1 This essay concerns what have been called "normative" or "justifying" reasons, considerations that count in favour of action. Normative reasons bear a different relation to practical reasoning. When a fact is a reason for A to φ in the normative or justifying sense, it need not be a reason for which she acts; she may not even be aware of it. But the fact is a premise for sound reasoning to a desire or motivation to φ whose further premises are available to A.2 This picture has been developed in different ways and in different idioms. Introducing a collection of essays on practical reason published in 1978, Joseph Raz appealed to "practical inference":