In this paper, I examine Wittgenstein’s conception of reason and rationality through the lens of his conception of reasons. Central in this context, I argue, is the image of the chain, which informs not only his methodology in the form of the chain-method, but also his conception of reasons as linking up immediately, like the links of a chain. I first provide a general sketch of what reasons are on Wittgenstein’s view, arguing that giving reasons consists in making thought and (...) action intelligible by delineating reasoning routes; that something is a reason not in virtue of some intrinsic property, but in virtue of its role; and that citing something as a reason characterises it in terms of the rational relations it stands in according to context-dependent norms. I then argue that on Wittgenstein’s view, we misconceive chains of reasons if we think of them on the model of chains of causes. Chains of reasons are necessarily finite, because they are anchored in and held in place by our reason-giving practices, and it is in virtue of their finitude that chains of reasons can guide, justify and explain. I argue that this liberates us from the expectation that one should be able to give reasons for everything, but that it limits the reach of reasons by tying them to particular reasoning-practices that they cannot themselves justify. I end by comparing and reconciling Wittgenstein’s dichotomy between chains of reasons and chains of causes with seemingly competing construals of the dichotomy, and I clarify its relation to the dichotomy between explanation and justification. (shrink)