This textbook introduces the reader to the field of phonology, from allophones to faithfulness and exemplars. It assumes no prior knowledge of the field, and includes a brief review chapter on phonetics. It is written within the framework of Cognitive Linguistics, but covers a wide range of historical and contemporary theories, from the Prague School to Optimality Theory. While many examples are based on American and British English, there are also discussions of some aspects of French and German colloquial speech and phonological analysis problems from many other languages around the world. In addition to the basics of phoneme theory, features, and morphophonemics there are chapters on casual speech, first and second language acquisition and historical change. A final chapter covers a number of issues in contemporary phonological theory, including some of the classic debates in Generative Phonology (rule ordering, abstractness, 'derivationalism') and proposals for usage-based phonologies.