The 1949 gathering was timed to coincide with the 100th anniversary of the Accademia Nazionale Luigi Cherubini in Florence. The setting was deliberate: Italy had not been a primary aggressor in the war, the city was relatively undamaged, and the centenary celebration provided cover for the work. The conference set three concrete tasks. First, update and verify Robert Eitner's monumental Quellen-Lexikon of 1900 to 1904, a ten-volume biographical and bibliographical dictionary of musicians that listed the location of every musical source the editor could trace; many of those locations no longer existed in 1949. Second, establish a central office in each country to microfilm musical sources from before 1800, so that the loss of any one library would not destroy the music itself. Third, standardize music cataloging across the languages and traditions of post-war Europe.

Two more conferences followed, in Luneburg in 1950 and in Paris in 1951. The Paris meeting was conducted under UNESCO's auspices, formally constituting the new association as part of the United Nations' broader effort to use cultural cooperation as an antidote to nationalism. The founders chose three official languages: English, German and French. They committed to annual conferences, a structure that has held continuously since the founding, including an online-only meeting during the 2020 pandemic. Membership grew from a small club into 1,100 members in 39 countries by 1969, and 1,850 members in 40 countries by 1991.

The most ambitious child of IAML is RISM, the Repertoire International des Sources Musicales, founded in 1952. RISM took on the original Florence task at industrial scale: locate, describe and make publicly available every surviving musical source from Greek antiquity through the year 1800. The project is still running. Its databases now describe hundreds of thousands of music manuscripts and early printed editions across hundreds of libraries on every continent, with new entries added every month. RISM has become the standard reference for any researcher trying to track down a particular early-music source, and it does what its founders dreamed of: it puts the music itself out of reach of any single catastrophe.

Three sister projects followed. RILM, the Repertoire International de Litterature Musicale, was founded in 1966 to index the scholarly literature about music: articles, books, dissertations, conference papers. Its two databases together cover everything from 1967 to the present and, through a retrospective project, the literature before 1967 as well. RIdIM, founded in 1971, deals with images: paintings, prints, drawings and photographs that depict musical instruments, performances and scenes. RIPM, founded in 1980, tackles the most fragile body of musical writing of all, the music periodicals published between roughly 1760 and 1966, which often survive only in fragmentary runs in scattered libraries. By 2014 RIPM had indexed 215 music periodicals, produced 306 printed volumes, and built a database of more than 726,000 annotated citations, with 166 journals available in full text through its online archive.

An organization founded in Paris with offices and projects scattered across the world is not strictly speaking a thing you can fly over. But IAML's reach into Germany has been steady and important from the start. The 1950 founding conference at Luneburg was held on German soil only five years after the end of the war, and German music librarians have been central to the association ever since. Local Oldenburg branches of the project work alongside the State Museum and the music collections of the regional library. There is a quieter geography to consider. Across Lower Saxony, music libraries from monastic foundations to municipal archives have spent the last seven decades doing the work IAML set out to do: counting what survived, cataloguing what was found, and ensuring that whatever happens next, the music is harder to lose this time.