Fluoroquinolones are an important group of antibiotics widely used in adult patients because of their excellent tissue penetration and their bactericidal activity. They are not authorised for paediatric use (except the limited indication of pseudomonas infections in cystic fibrosis), however, because of the potential for joint toxicity reported from experiments with young animals. Despite the absence of official approval, fluoroquinolones are widely used in paediatrics as second-line antibiotics when all other treatments have failed. Most of the information available about paediatric use concerns ciprofloxacin, which is used in children much more often than the other members of this class. The published paediatric series have shown that frequency of articular side-effects varies according to age: all the surveys have reported frequencies of around 0.1% in adults and 2-3% in children. Outside of cystic fibrosis and severe infections in which no other treatment is possible, the only paediatric situations where fluoroquinolones are superior to standard treatments for children, in speed of recovery and comfort as well as in efficacy, are typhoid fever, severe shigella dysenteries, and enterobacteria meningitis. Should the use of new fluoroquinolones active against pneumococci be authorised for upper respiratory infections (including recurrent otitis) in children, the potential emergence and dissemination of pneumococci strains in which multidrug resistance includes fluoroquinolones would create a real risk in the community. It is, therefore, important to continue the policy of second-line use in children, only after failure of an earlier treatment, and when other antibiotics approved for paediatric use cannot be used.