Gender is one of the most contested topics of our age, as ideologies are weaponised by the far right and real trans lives are targeted. But what are we talking about when we talk about gender? What are the origins of the concept itself, and where might it take us in the future?Rooted in decades of deep research and first-hand experience, Susan Stryker's sharp-eyed analysis invites us into her lifelong quest to uncover what gender means and does. From nineteenth-century phrenology to present-day anti-trans conspiracies to examples from her lifetime as an agenda setting historian, filmmaker and activist, Stryker finds surprising places to tune in to the origins, idiosyncrasies and generative possibilities of the gender concept.