This article attempts to illustrate the originality, depth, and farsightedness of Joseph Raz's conception, especially his idea that legal norms provide us with protected reasons to act, that is, with first-order reasons to behave as they prescribe, and with second-order, exclusionary reasons not to act for reasons against what they prescribe. But the article also highlights some aspects that raise doubts in my mind, especially with regard to the scope of these exclusionary reasons. This in two ways: by asking, on (...) the one hand, in what sense and subject to what limits legal norms provide exclusionary reasons for the organs entrusted with applying the law, especially for judges, and on the other hand, how and to what extent legal norms provide citizens with exclusionary reasons. So, in recognizing the strength of the Razian conception, the article also points to some of the difficulties it faces. (shrink)