1. Acknowledgements; 2. Introduction (by Hancil, Sylvie); 3. Part 1. General issues; 4. Acquisition Based and Usage Based Explanations of Grammaticalisation. An Integrative Approach (by Ohl, Peter); 5. Grammaticalization and Explanation (by Appelbaum, Irene); 6. The perfectivization of the English perfect: is it a case of grammaticalization, after all? The challenge of pluricentrality (by Walker, Jim); 7. Explaining language structure: On categorial misbehavior in Walman (Papua New Guinea) (by Heine, Bernd); 8. Toward a constructional framework for research on language change (by Traugott, Elizabeth Closs); 9. Part 2. Case studies; 10. Grammaticalization of Polish mental predicate prefixes (by Kokorniak, Iwona); 11. More Thoughts on the Grammaticalization of Personal Pronouns: Evidence from the history of Japanese (by Shibasaki, Reijirou); 12. The grammaticalization of nome in the Eastern Abruzzese dialect Ortese: Fromindefinite pronoun to inflectional marker? (by Russi, Cinzia); 13. The different developments of progressive aspect markers be in the middle/midst of and be in the process of V-ing: mechanisms of change (by Van Rompae, Tine); 14. Sequentiality in dialogue as a trigger for grammaticalization (by Haselow, Alexander); 15. The final particle but in British English: an instance of cooptation and grammaticalization at work (by Hancil, Sylvie); 16. "Final hanging but" in American English: Where a formal coordinator meets a functional subordinator (by Izutsu, Mitsuko Narita); 17. Author index; 18. Subject index