Why has Western thought been so persistent in its organisation of human bodies, and other categories, in terms of the binary opposition male and female? Is gender nothing more than an ideology, or does it have its basis in sexual difference? This invaluable introductory guide offers a clear overview of the concept, and problem, of gender. Claire Colebrook places the term in its historical contexts and traces its development from the Enlightenment to the present, before moving on to the evolution of the concept of gender from within the various stances of feminist criticism, and exploring recent developments in queer theory and post-feminism. Close analysis of key literary texts, including Frankenstein, Paradise Lost and A Midsummer Night's Dream, shows how specific styles of literature enable reflection on gender.