The genus Pseudomonas represents a large group of medically and envi ronmentally important bacteria. Interest in these bacteria is reflected in the extensive number of publications devoted to original research, re views, and books on this subject. In this volume selected areas of Pseu domonas research are presented in depth by persons who have been active in their fields over many years. The extensive reviews presented are an effort to provide a balanced perspective in a number of areas not readily available in the current literature. In the style of the previous Biotechnology Handbooks most of these topics have not been reviewed at all, and several are also presented from a new direction. For example, in addition to structural and compositional aspects, the chapter on lipids provides shifts in lipid parameters that result from environmental changes. This information will be invaluable to a cross section of Pseu domonas researchers in pathogenesis and bioremediation. The chapters presented include basic aspects of plasmid biology and carbohydrate metabolism and regulation. A major emphasis is placed on the Pseudomonas aeruginosa cell surface. Chapters cover lipo polysaccharide, capsular polysaccharide and alginate, the outer mem brane, transport systems, and the flagellum. Uptake of iron is also neces sarily an important portion of the chapter on iron metabolism.