This is the first full length history of the National Federation of Women Workers – a pioneering, all-female trade union operating from 1906 to 1921. It centres on the leaders, organisers, activists and members throughout the regions of Britain who built and sustained the union. By focusing on strikes, disputes and branch life, Hunt provides vital details of the working lives of thousands of women workers in the early twentieth century. The Federation, led by the charismatic Mary Macarthur, was influential out of all proportion to its size and attracted brilliant women activists to its campaigns, many of whom became well known in British Labour politics. By highlighting grassroots activism as well as national leadership, this work brings fresh perspectives to trade union history, deepening our knowledge of women who, whilst living through the political and social upheavals of the First World War, knew the realities of women's work that was too often dominated by low pay, poor conditions and inequality.