This introduction to the special issue on the future of work and working time offers an overview of issues of relevance to present-day debates on working time. The aim is to bring together two divergent debates, the first on working time reduction for full-time workers and the second on the diversification and fragmentation of working time. It considers the history of working time including the forces that led to the establishment of the standard employment relationship and to reductions in standard working hours. It addresses contemporary trends and examines why there has been both a stalling of working time reduction and a diversification of working time norms. Some limitations of focussing only on clock time are considered as well as some of the benefits, from more meaningful work to better health and well-being, that stem from both regular and non-excessive working time. The final section turns to the case for reform: it argues that policies are required to address the fragmentation of working time, and that these policies should be combined with a focus on shortening standard working hours that could increase the sustainability of working time in a dual-earner society and even limit the supply of labour for jobs offering only fragmented working time.