Twelve-hour days persisted in British and U.S. iron and steel after most industrial workers worked eight-hour days. When shorter hours finally came, sooner in Britain, they came abruptly. This article presents a model of working hours as public goods; when job attributes are shared there is a collective choice problem. In Britain, a collective bargaining mechanism reconciled the preferences of workers and capital owners and facilitated the move to shorter hours. In the United States immigrants had been willing to work long hours. When immigration was cut off, the government intervened.