An in-depth review of one of the most important classes of antimicrobial agents discovered in recent years. • Compiles the current information on a larger number of compounds and their expanding clinical applications. • Provides a knowledgeable summary of the problems and promises that quinolones hold for the scientific and clinical communities. • Includes information on the treatment of intra-abdominal infections and infections caused by intracellular pathogens and the use of fluoroquinolones in intensive care unit infections and in pediatrics. • Covers adverse effects, including QT prolongation, phototoxicity, effects on cartilage, and central nervous system effects.