The Société de l’Histoire du Protestantisme Français recently undertook a major renovation of its library, as the sanitary and environmental conditions of the basement level housing the periodicals and archival collections no longer met twenty-first-century standards. Preparatory studies were first undertaken from 2016 to 2018, together with the massive task of sorting, restoring, and moving collections. The renovation of the basement and the reading room was completed between October 2018 and June 2019. After the collections were restored to the revamped basement area, the library opened its doors to the public again in October 2019. Architects, librarians, Comité members, and library patrons all showed their fascination for the library, and willingly engaged themselves in service of the project. The same spirit is evident in the many deliberations and discussions involved, highlighting the enormity of the undertaking which rivals another, equally massive project – namely, the 1885-1886 transformation of a building on the courtyard of 54 rue des Saints-Pères into a library for the study of French Protestantism, which can now calmly await its future.