An estimated 350 hours of footage were shot. The editing process took 5 years.
Claude Lanzmann interviewed Jewish resistance fighter Abba Kovner in September 1979 for this film project. Lanzmann later decided to focus his epic film only on the dead, not on cases of Jewish, Polish, or German resistance or survival; therefore, this interesting interview and many others do not appear in the final version. All of the unused interview footage and outtakes produced for this film are available online as part of the 'Claude Lanzmann Shoah Collection' in the 'Steven Spielberg Film and Video Archive'. They are in the public domain now.
Some German interviewees were reluctant to talk and refused to be filmed, so Claude Lanzmann used a hidden camera, producing a grainy, black-and-white appearance. The interviewees in these scenes are sometimes obscured or distinguished by technicians watching the recording. During one interview, the covert recording was discovered, and Lanzmann was physically attacked. He was hospitalized for a month and charged by the authorities with "unauthorized use of the German airwaves".
According to Claude Lanzmann, the work on this film lasted from the end of 1973 until April 1985, almost 11 and a half years.