RISM was established in 1952 by the International Musicological Society and International Association of Music Libraries. The aim of RISM is to locate and catalogue all surviving musical sources dating from the earliest times to about 1850. Thirty-two countries are now working to catalogue source material in their libraries and archives, using the standards laid down by the RISM Central Office. RISM includes printed and manuscript music, works of music theory and libretti. The catalogues produced have become established as primary research tools for music, and are used worldwide by academics, students, performers and others to trace and identify music materials.