This Open Access book provides a comprehensive exploration of voice as a biomarker, addressing a current issue where engineers often analyze voice using sentences without describing or understanding voice as a set of defined parameters among others visually. This approach poses challenges for effectively treating voice disorders, as the features defined by engineers may not align with clinical needs.Stemming from the work of the Biomarker Committee group under the European Union of Phoniatricians (UEP), this book is the result of collaborative efforts and presents clinical studies aimed at bridging the gap between engineering analyses and clinical requirements.In recent years, many engineers have utilized software for voice analysis, often within continuous speech sequences, but without adequately defining voice features or specifying the choice of machine learning programs.Organized into 14 chapters, the volume begins with an overview of voice biomarkers and relevant literature, covering the fundamental physiology of voice biomarkers and examining voice pathology. The last chapters discuss genetics and molecular biology aspects.This book will serve as an invaluable resource for medical specialists in otolaryngology, phoniatrics, and neurology, offering insights and approaches to enhance the understanding and treatment of voice-related conditions.