Book excerpt: This volume and its companion one"Rethinking grammaticalization: New perspectives" offer a selection of papers from the "Third International Conference New Reflections on Grammaticalization," held at the University of Santiago de Compostela in July 2005. The overall aim of the book is to enrich our understanding of what grammaticalization entails via detailed case studies in combination with theoretical and methodological discussions. Some of the theoretical issues discussed in the sixteen articles included in the volume are the nature of grammaticalization and related processes such as anti-, re- and degrammaticalization, the relationship between grammaticalization and lexicalization, the role of frequency in grammaticalization and the interplay between information structure and grammaticalization. Other topics covered are the grammaticalization of composite predicates in English, the emergence of modal particles in German and particle clusters in Dutch and the grammaticalization of various modal auxiliaries in Spanish and in Swedish.