This issue of Medical Clinics of North America brings the physician up to date on the newest agents for antibacterial therapy.� New drugs are covered, as well as new approaches.� Topics include the newer fluoroquinolones; epidemiology, molecular mechanisms, and clinical management of pathogens resistant to antibacterial agents; current use for old antibacterial agents, including polymyxins, rifamycins, and aminoglycosides; topical antibacterial agents; newer beta-lactam antibiotics, including doripenem, ceftobiprole. ceftaroline, and cefepim; the use of antibacterial agents in renal failure; antibiotics for gram positive bacterial infections, including vancomycin, teicoplanin, quinupristin/dalfopristin, oxazolidinolones, daptomycin, telavancin, and ceftaroline; as well as macrolides, ketolides, and glycylcyclines, including azithromycin, clarithromycin, telithromycin, and tigecycline.