The view that reductions in working hours are an efficient means of reducing unemployment seems to have as many lives as a cat. Although repeatedly refuted, it pops up again and again. The trade unions of the European Community (ETUI 1979) and the Nobel laureate Wassily Leontief (1979, 1982) have been eager proponents of this policy proposal. In Sweden, however, it has never won many adherents either among trade unions, academic economists or in the public opinion. In this chapter, I argue that the clearsightedness of Swedish unions may to some extent be attributable to the thorough analysis of this issue by Swedish economists, to their view of the causes of unemployment and to the fruitful intellectual exchange between academic economists and labour leaders. Extending over the period 1889-1935, this chapter starts with an account of the early labour movement’s demand for the 8-hour working day and the criticism of the demand delivered by Knut Wicksell. The actual reductions in working hours that took place during the period, including the introduction of the 8-hour day, are then discussed. Next, the analyses by Swedish economists of the effects of the 48-hour week are presented. Finally, I discuss why the Swedish unions did not embrace reduced working hours as a remedy against unemployment.