Primarily includes correspondence dating from the late 1920s until the late 2010s received by René Char and Marie-Claude Char. Correspondents include: Pierre-André Benoit, Éditions Gallimard, and others publishers; Yves Bonnefoy, Pierre Boulez, René Magritte, Joan Miró, Man Ray, Anna Seghers, Tristan Tzara, and other authors, critics, editors, translators, journalists, artists, and musicians; as well as some letters from Char, including those to Georgette Goldstein, his first wife, and to Marie-Claude Char. Related documents, manuscripts, photographs, ephemera, and printed materials accompany some of the correspondence. Some of this includes materials about correspondents that Marie-Claude Char presumably added to the collection. Some letters correspond with René Char's time with the French Resistance during World War II.

Some letters, including those from Louis Aragon, Albert Camus, Paul Celan, and other major French authors to Char are copies; the originals were either donated or sold to other libraries and repositories. Their location is often noted in the description for each correspondent.

Also included is posthumous correspondence of Marie-Claude Char with dealers and correspondents. Some of the letters relate to publications about René Char.

While many of the correspondents have been identified, there is a run of chronological correspondence that may contain letters from those who have been identified elsewhere in the collection.