During the last decade of the 20th century there have been numerous advances in the area of rhodium-catalyzed hydroformylation, such as highly selective catalysts of industrial importance, insights into mechanisms of the reaction, very selective asymmetric catalysts, in situ characterization and application to organic synthesis. The views on hydroformylation which still prevail in textbooks have become obsolete in several respects. This volume contains a series of chapters discussing several rhodium systems arranged according to ligand type, including asymmetric ligands, a chapter on applications in organic chemistry, a chapter on modern processes and separations, and a chapter on catalyst preparation and laboratory techniques. It concentrates on highlights, rather than a concise review and aims at an audience of advanced students, experts in the field, and scientists from related fields. The didactic approach should also make it useful as a guide for an advanced course.