A profound shift is occurring in the nature of advanced industrial economies. We are moving towards a 'networked economy' in which firms must respond to greater competition, globalisation, changing consumer demands and other business changes. These firms require a new kind of workforce, which is 'flexible' and 'adaptable'. These factors are at the core of the development of atypical work forms. Workers engaged in 'atypical' work (work timing, work contracts, work location) remain the minority, but are becoming an increasingly significant minority and the pace of change is accelerating in the 1990s. This trend has clear social impacts and poses important challenges, such as the future of labour law or the future of the Welfare State. Some of atypical work forms (most obviously part-time working) are long-standing and pre-date recent developments. However, the core institutions are playing a role in the extension of several of these practices. We have considered atypical work patterns under four headings.