Book excerpt: The neotropical primate family Pitheciidae consists of four genera Cacajao (uacaris), Callicebus (titis), Chiropotes (bearded sakis) and Pithecia (sakis), whose 40+ species display a range of sizes, social organisations, ecologies and habitats. Few are well known and the future survival of many is threatened, yet pitheciines have been little studied. This book is the first to review the biology of this fascinating and diverse group in full. It includes fossil history, reviews of the biology of each genus and, among others, specific treatments of vocalisations and foraging ecology. These studies are integrated into considerations of current status and future conservation requirements on a country-by-country basis for each species. A state-of-the-art summary of current knowledge, Evolutionary Biology and Conservation of Titis, Sakis and Uacaris is a collective effort from all the major researchers currently working on these remarkable animals.