Exacerbations of chronic bronchitis (AECB) are a major cause of morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD), and their impact on public health is increasing. The new fluoroquinolones have an excellent spectrum providing cover for the most important respiratory pathogens, including atypical and "typical" pathogens. Not surprisingly, different guidelines have inserted these agents among the drugs of choice in the empirical therapy of AECB. The pharmacokinetic and dynamic properties of the new fluoroquinolones have a significant impact on their clinical and bacteriological efficacy. They cause a concentration-dependent killing with a sustained post-antibiotic effect. This review discusses the most recent data on the new fluoroquinolone prulifloxacin and critically analyses its activity and safety in the management of AECB.