How is linguistic theory related to linguistic practice? What do theoretical notions and models tell us about real-life language use? Are there any limits to what such notions and models can reasonably be taken to accomplish? These questions are fundamental to any serious investigation into the phenomena of human communication. The essays in this book show that philosophers and linguists of quite different brands have tended to give undue priority to their own favourite theoretical framework, and have presupposed that the descriptive scheme invoked by that framework constitutes a pattern to which any linguistic practice somehow has to conform. What unites the contributors to this volume is a critical attitude towards such essentialist aspirations. By investigating several concrete examples of this tendency - examples collected from such seemingly disparate areas as structuralism, contemporary analytic philosophy and feminist epistemology - the authors collectively manage to cast doubt on the very attempt to fit the whole of linguistic practice into a general theoretical mould.