Book excerpt: This second book in the three-volume Plant Secondary Metabolites covers the stimulation, extraction, and utilization of plant secondary metabolites, which are organic compounds that aid in the growth and development of plants but which are not required for the plant to survive by fighting off herbivores, pests, and pathogens. These plant secondary metabolites have been used since early times in various medicines and food products for beneficial health purposes and are still relevant and popular today.