This book explores how one measures and analyzes human alterity and difference in an interconnected and ever-globalizing world. This book critically assesses the impact of what has often been dubbed 'the ontological turn' within anthropology in order to provide some answers to these questions. In doing so, the book explores the turn's empirical and theoretical limits, accomplishments, and potential. The book distinguishes between three central strands of the ontological turn, namely worldviews, materialities, and politics. It presents empirically rich case studies, which help to elaborate on the potentiality and challenges which the ontological turn's perspectives and approaches may have to offer.