This volume provides a systematic, comprehensive, and easy to understand background material on functional groups and isomerism for formal courses in pharmacy and medicinal chemistry, biotechnology, clinical biology or biochemistry, as well as to practitioners. This textbook is comprised of two parts: the first part focuses on organic functional groups, paying attention to the IUPAC nomenclature for naming organic compounds, and to the physical and chemical properties of functional groups found in organic biological compounds, whereas the second part focuses on introduction to and classification of isomers, structural isomers, and stereoisomers. Knowledge of isomerism has helped pharmacists and pharmaceutical scientists in introducing safer and more effective drug alternatives of the newer as well as existing drugs. The structured presentation, highly graphical nature on the text and practice problems will provide an instrumental framework and aid to revision for students preparing for examinations.