A first approximation toward a comprehensive policy of nighttime construction work based on the explicit consideration of the following three main aspects is presented: (a) the travel time savings produced by nighttime construction work, (b) the impact that nighttime work has on workers' human factors (e.g., sleep deprivation and disruption of family and social lives), and (c) the impact that pay differentials for nighttime workers would have on project costs. Other aspects such as quality of work and inspection were not studied because of project constraints. The travel time and economic savings of nighttime work were estimated by means of traffic simulations for a typical case. The human factor analyses relied on field surveys and interviews with workers. This research found ample evidence that indicates that nighttime work produces (a) negative impacts on the workers' sleep patterns, body rhythms, and social and family lives and (b) significant economic savings in terms of travel time to motorists. A set of policy recommendations is discussed and analyzed.