Constitutional and legislative restrictions on the timing of legislation and regulation are ubiquitous, but these “timing rules” have received little attention in the legal literature. Yet the timing of a law can be just as important as its content. The timing of a law determines whether its benefits are created sooner or later. This determines how the costs and benefits are spread across time, and hence how they are distributed to the advantage or disadvantage of different private groups, citizens, and governmental officials. We argue that timing rules are, and should be, used to reduce agency problems within the legislature and between the legislature and the public, and to mitigate deliberative pathologies.