This book is primarily the result of the Leaf Beetle research presented at the Fifth International Symposium on the Chrysomelidae, held on 25-27 July 2000 in conjunction with the XXI International Congress of Entomology, in Iguassu Falls, Brazil. It is a collection of papers by leading experts on Leaf Beetles from over 15 countries discussing their research on all 5 major continents concerning systematics, diversity, phylogeny, biology, ecology, genetics, etc. This compilation on such diverse topics about Chrysomelidae is dedicated to Dr. P. H. A. Jolivet who is a kind of grandfather to all the world's Leaf Beetle workers. Some chapters discuss biological diversity of the primary tropical rainforests of Costa Rica, Panama, Brazil and Central and East Africa and other chapters discuss the biodiversity in the Nepalese Himalayas, Central Europe, etc. The papers cover almost all the Leaf Beetle subfamilies in the broad sense with special detailed treatment of 9 of these subfamilies. Some papers use morphology to consider the classification of certain groups, whereas molecular DNA studies are used for other groups. In some chapters immatures are treated morphologically and in others their natural enemies are discussed. Host plant diversity and choice are considered as well as feeding behavior. Chemical defense is interestingly discussed in several chapters concerning eggs, larvae and adults. Polymorphism of color pattern and flight ability are the subjects for two contributions. In many chapters genetics and ecology as well as pure biology or natural history are prevalent themes. This book will be an indispensable tool to anybody interested in leaf beetles as well as to specialists in taxonomy, phylogeny and biogeography, applied entomology, ecology, genetics etc.