This book is the result of an international symposium on gall-inducing arthropods, which was held September 5-9, 2005, in Kyoto, Japan. It was organized as the 4th international symposium on gall-inducing insects and as the symposium of the In­ ternational Union of Forestry Research Organizations (lUFRO) working group, 7.03.02, Gall-Inducing Insects. The book addresses recent developments in the ecology, evolution, systematics, physiology, and biodiversity of gall-inducing arthropods, with individual contri­ butions ranging in scope from detailed descriptions to profoundly synthetic stud­ ies. One underlying theme of the book is the various impacts of gall induction that indirectly affect insect communities on the host plant. The other important contri­ bution is the highly intricate and dynamic interactions between galling arthropods and their uniquely specialized host plants. Included also are chapters that discuss biodiversity and distribution patterns of gall-inducing arthropods, and biological control of invasive gall-inducing arthropods and of invasive trees. We believe that this book makes an important contribution to the knowledge of galling arthropods and their associates and to the development of robust, general principles of the ecology and evolution of these organisms.