Luteolin belongs to a group of naturally occurring compounds called flavonoids that are found widely in the plant kingdom. Luteolin is widely present in many fruits, vegetables and medicinal herbs. It has many beneficial health effects, including antioxidant, anti–inflammatory, anti–proliferative, proapoptotic, and anti–angiogenic. This book discusses the natural occurrences of luteolin, as well as the therapeutic applications and health effects.