Background - An outbreak of colonization with glycopeptide-resistant enterococci (GRE) began at the Nancy University Hospital in late 2004. Despite the implementation of appropriate measures, it spread to other healthcare facilities in the Lorraine region in early 2007. A special task force was deployed by the Regional Hospital Agency to control the outbreak at the regional level. Action phases - Over the course of four months, two successive phases were carried out, during which the task force first visited the affected facilities and conducted an assessment. It then provided daily support to the facilities, distributed a list of facilities affected by the ERG to optimize the screening and probabilistic isolation policy surrounding transfers (without paralyzing the entire Lorraine healthcare system), and developed a summary document outlining procedures for managing an ERG outbreak. This epidemic, which affected more than 900 patients, continued to spread through the first quarter of 2008, before a sharp decline in the number of new cases was observed. Conclusion - The implementation of national recommendations—adapted, supplemented, and harmonized according to local specificities—appears to have enabled the control of an ERG outbreak that was already well established in a French region. (R.A.)