This book offers a comprehensive perspective of herbal medicine phytochemistry and explores the application of plant extracts as bioactive compounds in disease prevention and treatment in modern or traditional medicine. The book starts with an introduction to the history and value of herbal medicine, followed by 3 parts covering the main phytochemical components and metabolites in herbal medicine, different uses and practices in herbal medicine, including a region-wise analysis of methods and practices and an overview of regulations and policies for herbal medicinal practitioners, and the advances and challenges in quality assessment of herbal medicine. Plants generally have the tendency to bioaccumulate trace metals from the environment and they are easily contaminated by microorganisms from water sources and poor hygiene practices of the herbalist. Quality assessment and assurance is, thus, a pertinent challenge in herbal medicine practice (i.e., in remedy formulation and application), and this book offers an authoritative perspective on this topic, covering aspects such as quality control strategies, preparation techniques, chemical quantification in phytomedicine, and the efficacy and safety of herbal remedies. Moreover, in this book, readers will find valuable insights into the latest trends and developments in the field, and a critical review of the application of medicinal plants to treat cardiovascular, digestive, respiratory neurological and reproductive diseases. Particular attention is given to the advances and trends in the field, and readers will learn about the latest biotechnological approaches, the use of nanotechnology in herbal medicine, metabolomic analysis of medicinal plants, big data application in herbal medicine, and the value of herbal medicine towards sustainability. Given its breadth, this book is aimed at researchers, academics, practitioners and professionals working in the fields of natural, life, health, clinical, and biomedical sciences, and interested in herbal remedies, pharmacology, pharmacognosy, human nutrition and dietetics, plant biology, and biotechnology/microbiology.