The archive at Sheffield contains 170 CD-ROMs of interviews with theatre workers and audience members, including Glenda Jackson, Brian Rix, Susan Engel and Michael Frayn. There is also a collection of copies of correspondence between Gyorgy Lengyel and Michel and Suria Saint Denis, and between Gyorgy Lengyel and Sir John Gielgud, dating from 1958 to 1999.