World production of citrus fruits is still growing. At present, about 30 percent of that yield is devoted to industrial production, mostly on those essential oils and juices used in foods, pharmaceuticals, and cosmetics. Covering research reported in the literature over the past ten years, this book presents the most current research available on the analysis, composition, and biological activity of citrus products, as well as concerns with adulteration and contaminants. The research group currently coordinated by the editors at the University of Messina has been investigating citrus essential oils since the 80s and is known worldwide for its development of chromatographic investigation methods.