Forty patients were treated with ofloxacin for community acquired lower respiratory tract infections. Eighteen pathogens were isolated in sputum; Streptococcus pneumoniae (4) and Haemophilus influenzae (4) were the most common, followed by Klebsiella pneumoniae (3), Klebsiella spp. (2), Staphylococcus anreus (2), Pseudomonas spp. (2), and Pseudomonas aeruginosa (1). Ofloxacin 200 mg every 12 hours was administered for an average of 3.7 days intravenously followed by 5.4 days orally. Response to therapy was judged to be cure in 38 (95%; 95% C.I., 85%-95%) patients, failure in one (2.5%) and "indeterminate" in one (2.5%).