This volume of Progress in Brain Research provides a synthetic source of information about state-of-the-art research that has important implications for the evolution of the brain and cognition in primates, including humans. This topic requires input from a variety of fields that are developing at an unprecedented pace: genetics, developmental neurobiology, comparative and functional neuroanatomy (at gross and microanatomical levels), quantitative neurobiology related to scaling factors that constrain brain organization and evolution, primate palaeontology (including paleoneurology), paleo-anthropology, comparative psychology, and behavioural evolutionary biology. Written by internationally-renowned scientists, this timely volume will be of wide interest to students, scholars, science journalists, and a variety of experts who are interested in keeping track of the discoveries that are rapidly emerging about the evolution of the brain and cognition.