At some point while studying at Ruskin College my tutor gave me the following essay title, ‘Given the success of the Transport and General Workers Union, why does Britain need more than one union?’ Although I can't now remember what my essay concluded, the question provoked a line of thinking which led to this book. While UK trade unions started in trades, later developing general and industrial forms, it is general unions that now predominate in membership. However, the vast majority of unions certified in Great Britain are not general and project a variety of identities, raising critical questions that this book addresses. These include explaining the diverse identities projected by contemporary trade unions, the primacy of general unions, the persistence of what are termed ‘niche unions’ in this work and the efficacy of this complex array of identities in recovering unions lost power and influence, restoring lost membership and organizing the unorganized.