The book provides an overview of cortisol, an essential hormone for survival, from the perspective of a multidisciplinary team of international experts, offering an evidence-based perspective on the topics addressed. It presents aspects of the hormone's secretion, transport, metabolism, and regulation, as well as its intricate mechanisms of action. The role of cortisol in various pathologies is also addressed professionally. We hope that this book will answer the many questions raised by cortisol and provide readers with valuable information for their everyday clinical practice.