The ongoing exploration of medicinal plants has revealed crucial information about potential pharmacological targets, including cancer, HIV/AIDS, Alzheimer disease, malaria, and inflammation. A number of natural product drugs derived from plants have been successfully commercialized as dietary supplements or chemo-preventive agents, while others are currently undergoing clinical trials. This book sheds light on the innovative approach of integrated drug discovery, which combines traditional wisdom and documented use with the discovery of drugs from plant sources.