Ionic silver is an antimicrobial agent included in wound dressings to prevent and manage local wound infection. As silver content varies considerably between dressings, an in vitro study was conducted to investigate the antimicrobial activity of a variety of silver-containing foam dressings. The results showed considerable variation in the ability of the different silver-containing foam dressings to control wound pathogens. Dressing structure, rather than silver content, was found to be a significant factor in the observed differences in antimicrobial performance between the foam dressings.