This important volume commences with an overview of the modes of action of defensive secondary metabolites, followed by detailed surveys of chemical defense in marine ecosystems, the biochemistry of induced defense, plant-microbe interactions and medical applications. A chapter is also included covering biotechnological aspects of producing valuable secondary metabolites in plant cell and organ cultures. This is a comprehensive and fully updated new edition, edited by Professor Michael Wink and including contributions from many internationally acknowledged experts in the field.