Recent research indicates that plants may be defended by mechanisms activated only after a plant has been challenged by a herbivore. Examines these inducible defenses and provides a framework for future advances in the field. Also serves as a summary and compilation of major studies to date on important areas of plant and insect ecology. While treating both vertebrates and invertebrates it covers mechanisms and models of long- and short-term induction. The impact of inducible phytochemicals on herbivores is extensively discussed as are pesticidal activity of inducible phytochemicals. Covers agricultural implications of inducible phytochemicals.