This book provides the first comprehensive treatment of Albert the Great's (c. 1193-1280) notion of virtus formativa, a shaping force responsible for crucial dynamics in the formation of living beings. Crossing the boundaries between theology and philosophy, the notion of virtus formativa, or formative power, was central in explaining genetic inheritance and the configuration of the embryo. By adopting an interdisciplinary approach, this book reconstructs how Albert the Great, motivated by theological open issues, reorganised the natural-philosophical and medical theories on embryonic development, creatively drawing upon Greek, Patristic, and Arabic sources. A valuable contribution to research, this book offers essential insights for those studying the history of embryology, medicine, and science in the medieval and renaissance periods. Amalia Cerrito is an Associate Member of the Centre for the Studies of Medicine and the Body in the Renaissance (CSMBR) of Pisa, Italy. Having studied the history of medieval philosophy at the Universities of Pisa and Florence, she has published journal articles on the interaction between natural philosophy and the biblical exegesis of Albert the Great. Amalia's recent publications are devoted to the theoretical background of Albert the Great's natural philosophy and Neoplatonism's influence on his theories of zoology, botany, and embryology.