The Rockefeller Commission for the Prevention of Tuberculosis in France played a key role in public health reforms in post–World War I France. In May 1920, one of the commission’s traveling units whose goal was to bring health education to the French departments toured the Grand-Duchy of Luxembourg. This article discusses this ten-day campaign as a trigger for comprehensive public health reforms in Luxembourg. By the 1920s the steel industry had become the country’s dominant economic sector, with the conglomerate Arbed as the main employer in constant need of a healthy workforce. A group of Luxembourgian anti-tuberculosis activists, spearheaded by the wife of the country’s foremost industrialist, tried to benefit from the Rockefeller projects in France. Throughout the following decades, Luxembourgian anti-tuberculosis activists maintained close contacts with French experts. This article traces the transnational circulation of public health knowledge in the interwar period and elucidates Luxembourg’s geostrategic repositioning after World War I.