Emergence refers to the occurrence of properties in a structure that its individual elements do not possess. Phenomena of emergence are ubiquitous and can be observed, for example, in the V-formation of a flock of birds or in consciousness, which is based on neural processes that themselves do not have consciousness. This concept is also present in the social realm, such as in groups or societies. Emergence is often associated with the thesis that the emergent properties of complex structures cannot be reduced to the properties of their elements and therefore require their own explanatory approaches. However, this view contradicts the aspiration for a comprehensive explanation of reality. The contributions in this volume explore the tension-filled relationship between emergence and reduction from the perspectives of various sciences: philosophy and sociology.