Based on recent guidelines for the management of community-acquired pneumonia, this study was designed to evaluate the effectiveness of a new fluoroquinolone compared with standard antimicrobial regimens, in conditions relating as closely as possible to the real world setting.In this study, 564 patients were randomised to either oral moxifloxacin (400 mg o.d.) or to standard oral therapy (amoxicillin 1 g t.i.d. or clarithromycin 500 mg b.i.d. alone or in combination) for up to 14 days using a double-blind procedure. The choice between the three standard regimens was made by the clinician prior to randomisation. Clinical response, quality of life, symptoms, healthcare resources and safety were assessed.In the per-protocol population, clinical success was reported for 201 of 215 (93.5%) and 217 of 231 (93.9%) in the moxifloxacin and standard groups, respectively, at 7-10 days post-therapy. At 28-35 days follow-up, continued clinical cure was observed in 183 of 192 (95.3%) moxifloxacin and 207 of 221 (93.7%) standard groups. Drug-related adverse events were reported in 55 of 274 (20%) moxifloxacin and 86 of 279 (31%) standard patients with diarrhoea w5%.Oral moxifloxacin monotherapy was as effective as, and better tolerated than, optimal antibiotic strategy represented either by mono-or combination therapy (amoxicillin and/or clarithromycin) in community-acquired pneumonia management.