What do all languages have in common, and what gives each language its individuality? These typological questions are fundamental to linguistic theory. This collection comprises original contributions from leading scholars of the major schools of contemporary typological research, from the Prague School to the Generative Grammar tradition. Each contributor presents the theoretical foundations and practical achievements of his or her approach to language typology; the whole provides a unique overview of a field characterized by its diversity. Contents: 1. Approaches to Language Typology: A Conspectus, Masayoshi Shibatani and Theodora Bynon 2. Typological Comparison: Towards a Historical Perspective, Paolo Ramat 3. Prague School Typology, Petr Sgall 4. Modern Syntactic Typology, William Croft 5. The Diachronic Typological Approach to Language, Joseph H. Greenberg 6. Typological Research on Actancy: The Paris RIVALC Group, Gilbert Lazard 7. The St Petersburg/Leningrad Typology Group, Vladimir P. Nedjalkov and Viktor P. Litvinov 8. Cognitive-Conceptual Structure and Linguistic Encoding: Language Universals and Typology in the UNITYP Framework, Hansjakob Seiler 9. The Principles-and-Parameters Approach: A Comparative Syntax of Engish and Japanese, Naoki Fukui