Marine Natural Products - Diversity and Biosynthesis contains four chapters, which review some of the most lively research topics in the field, all written by active contributors.Steroid chemistry, the glamor area of natural product research in the years following World War II, was replaced by macrolides, alkaloids, and prostanoids. Sterol chemistry again became exciting when an unanticipated rich diversity of marine invertebrate sterols were isolated, notably from sponges. After pioneering research in Italy, the field was reborn in Carl Djerassfs laboratory at Stanford. As a result, we now have a better and more detailed knowledge of sterol biosynthesis than of any other class of marine natural products. The authors of Chapter 1 are Stanford alumni.Naturally occurring isocyano compounds are no longer an oddity since their frequent isolation from members of the class of Demospongiae. Their biogenesis has intrigued chemists ever since the first terrestrial isocyano compound (an amino-acid derivative) was described from a micro-organism. All known marine isocyano compounds are terpenoid and their biosynthesis continues to pose an unsolved problem, which is discussed in Chapter 2.Early natural product research with marine mollusks supported a conclusion that all secondary metabolites of mollusks are diet-derived, which proved to be premature. In fact, the biosynthetic capability of some marine mollusks covers a wide spectrum of chemical classes and substances. Much of this recent insight has resulted from work in the laboratories of the authors of Chapter 3.Oxylipin is a term that has not yet fully entered the scientific vocabulary. Indeed, a new word for oxidized fatty acid-derived compounds was needed, as the older terms - prostanoids, eicos-anoids proved to be too narrow for an ever-widening spectrum of discoveries. Much of this research has come from the laboratory of the authors of Chapter 4. Their account demonstrates the diversity and highlights some of the unique biosynthetic pathways of oxylipins.