Utilizing over 200 full-color photos of tongue pathologies and a practical, concise text, this work explains the application and significance of tongue presentation in the diagnosis and treatment of common diseases. Chapter 1 explores fundamentals of tongue diagnosis, including the relationship of the tongue to the organs, channels, qi, blood, and fluids; important markers in diagnosis, and a comparison of the tongue reflecting normal and pathological states. Chapter 2 covers diagnosis of tongue quality, e.g., vitality, color, shape, condition, and vessel appearance. Chapter 3 covers diagnosis of the tongue coating, including qualities and colors of the coating. Chapter 4 elucidates the clinical significance of tongue diagnosis and its clinical application to diseases of the various zang fu.