Between October 2005 and September 2006, all European Union member states were required to carry out standardised surveys of the prevalence of Salmonella in broiler flock holdings to establish baseline data from which to derive national targets for disease reduction. In the uk 382 holdings were sampled, 41 of which were positive for Salmonella, giving an estimated weighted prevalence of 10·7 per cent (95 per cent confidence interval [ci] 8·1 to 13·1 per cent). The serotype most frequently isolated was Salmonella Ohio, with a weighted prevalence of 2·2 per cent (95 per cent ci 1·2 to 3·7 per cent), followed by Salmonella Kedougou at 1·7 per cent (95 per cent ci 0·9 to 3·2 per cent). There were no isolates of Salmonella Enteritidis and only a single isolation of Salmonella Typhimurium (0·2 per cent, 95 per cent ci 0·0 to 1·6 per cent). Of the three other serotypes given top priority by the eu owing to their public health significance, Salmonella Virchow was isolated from one holding, but Salmonella Hadar and Salmonella Infantis were not detected on any of the holdings.