From galagos to gorillas, the primates of western Uganda comprise a very di­ verse collection of species. Western Uganda has a long history of primatological research extending back to the publications of the Uganda Virus Institute in 1947 and even to the notable first encounters of Count Beringe with moun­ tain gorillas in 1913. Many forested areas of Uganda (Figure i) have been the focus of research continuously since 1970, and thus western Uganda has a cen­ tral place in primatology that it maintains to the present day. In this book, we present a series of new, unpublished scientific accounts of a selection of the species in the region, each chapter focusing on one or more particular characteristics of the species concerned. The book falls naturally into four sections. First, we introduce the primates of western Uganda, with a chapter on their tax­ onomy. We have left authors to follow the taxonomic terminology with which they are most comfortable, but present this first chapter to reflect recent developments in the understanding of taxonomic relationships among the Ugandan primates. Second, we present a section with an ecological focus, followed by a collection of chapters on behavior and physiology. Finally the focus shifts to conservation. Chimpanzees and gorillas have always attracted a lot of interest both among the general public and among researchers; consequently, this interest is reflected in the present volume.