This chapter introduces general union identity, drawing a clear distinction between what are termed ‘true general unions’, including Unite and GMB, which are prepared to recruit virtually any worker into membership, and ‘niche general unions’ that project some niche characteristics by organising either horizontally, as in the case of Prospect, which is a ‘horizontal general union’, or vertically as with Unison, which is a ‘vertical general union’. A further distinction is drawn between major general unions, all of which were observed to practice niche unionism through sectionalised structures and minor general unions that tend not to do so. The chapter explores the observable characteristics of general union identity together with the impact of mergers, membership benefits, affiliations and political alignment. The work also considers what are termed ‘new generation unions’ such as IWUGB, some of which project a general union identity.