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 In this book, we present a series of new, unpublished scientific accounts of a selection of the species in the region, each chapter focusing on one or more particular charac­ teristics of the species concerned.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 devel­ opments 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.