The IISH reference library contains relevant publications on French political history, social conflicts, and relationships. Given the importance of intellectuals in the social movement, their history is essential, and the library has the complete works of important thinkers in various editions. The atheist socialist Sylvain Maréchal, the Icarian Etienne Cabet, and the early socialist Jean-Charles-Leonard Simonde de Sismondi are just three examples. In addition, the publications of the movements themselves, such as periodicals and leaflets, are available for research. The libertarian and literary magazines l'Endehors and La Feuille, both creations of the free spirit Zo d'Axa (1864-1930), are in the IISH library. Along with the papers of Eugène Humbert and his wife, advocates of birth control and free love, many books, photographs and serials came to the Institute, including the journals Régéneration (1896-1908) and Génération Consciente (1908-1914). In the estate of the Russo-French revolutionary socialist Sania Gontarbert a collection of Front Ouvrier, an illegal French Trotskyist journal 1942-1944, surfaced.
The Institute's audio-visual department contains a wealth of iconographic and sound materials on the socialist, communist, and anarchist movements (from orthodox to dissident), as well as trends in the trade union movement. Outstanding are hundreds of portraits of Communards made by the photographer Eugène Appert that were once included in the Descaves collection. The original posters produced by Atelier Populaire during the May '68 revolt in Paris are in the IISH Image and Sound collection along with many other materials.
All these library and Image and Sound collections can be retrieved through different types of searches in the IISH catalogue.