The low status accorded to part-time workers in Japan has resulted in huge inequalities in the workplace. This book examines the problem in-depth using case-study investigations in Japanese workplaces, and reveals the extent of the inequality. It shows how many part-time workers, most of whom are women, are concentrated in low paid, low skilled, poorly unionised service sector jobs. Part-time workers in Japan work hours equivalent to, or greater than, full-time workers, but receive lower financial and welfare benefits than their full-time colleagues. Overall, the book demonstrates that the way part-time work is constructed in Japan reinforces and institutionalises the sexual division of labour.