A recent study of 550 Canadian companies with 50 or more employees found that firms which have moved to a four-day week report higher productivity and staff retention than those keeping the standard five days. Even so, only about a fifth of firms have made the switch. The study, says its author Elliot Marsh, raises the question of why the shift is so slow to spread and how it is best encouraged. "It matters," Marsh says, "because in twenty-first-century Canada people like to believe, rightly or wrongly, that a shorter week rewards focus, not idleness."

Sophie Renaud, who teaches organizational behaviour at the University of Alberta, argues that the slow uptake is mainly for employees themselves to fix, since it stems from the wary way they treat a change in their routines. Whereas some workers will happily rethink how they spend an afternoon, she maintains, most cling to old habits until they are certain the shorter week will not expose them. "A good many people regard finishing early as somehow cutting corners," Renaud observes, "and that caution keeps them chained to the desk, which is ironic, since the diligence it reflects is exactly what a compressed week rewards. The remedy, in the end, lies with workers, who simply need to trust the arrangement."