It has been said that norms can solve collective action problems. To endorse a norm is to hold a normative belief. This article insists that we try to isolate moral motivation - motivation by moral belief - as such, and that its existence cannot be taken for granted. Accepting the Humean view that belief alone cannot motivate, the article rejects the thesis that there is a necessary or conceptual connection between moral belief and motivation; it warns that in looking for motivational powers or effects of normative belief we must take care to rule out the possibility that the motivation is merely derived from existing desires; and it argues that deliberation and evaluation do not produce desires purely out of beliefs. These considerations are among the necessary preliminaries to getting clear about the role of ‘social capital’ in solving collective action problems.