The collection consists almost entirely of correspondence to and from Carr, together with a few folders of additional material such as name tags from science fiction conventions, assorted fannish writings from Carr, and miscellaneous ephemera.

The correspondence documents Carr's long and extensive activity as a science fiction fan and fanzine editor. Included are letters between Carr and prominent fannish figures such as Forrest J. Ackerman, Redd Boggs, Terry Carr, Richard Eney, Donald Franson, Lynn Hickman, Ralph Holland, Seth Johnson, Janie Lamb, Vernon McCain, Orville Mosher, Bruce Pelz, Boyd Raeburn, Roy Tackett, Bjo Trimble, Harry Warner, Walter Weber, and Walter Willis. Many of Carr's letters, however, are to and from ordinary fans. Carr's fannish correspondence details her views on science fiction and fantasy media and fandom, convention attendance, the publication of her own fanzines, and her political and administrative involvement with such fan organizations as the National Fantasy Fan Federation (N3F). This portion of the collection contributes much to the understanding of the personalities, issues, and feuds that dotted mid 20th-century SF fandom.

Some of the correspondence consists of so-called "round robins", cyclical communications among a small number of fans.

The collection also contains letters that Carr exchanged with several well-known science fiction writers, including Gregory Benford, Robert Bloch, and Jack Chalker. Of particular interest and depth are three folders of correspondence between Carr and Marion Zimmer Bradley, in which both women discuss at length their religious and philosophical beliefs.

Much of Carr's correspondence concerns her political and social beliefs. Carr was a believing, practicing Roman Catholic and not shy about publicizing her religious views. She was also a deeply conservative Republican, and many of her letters detail her strong and often caustic opinions about U.S. presidents from Dwight D. Eisenhower through Jimmy Carter, Communism, American liberals, the Cold War, the anticommunist crusade of Senator Joseph McCarthy (of whom she was a strong supporter) and other topics. Carr's right-wing views often provoked controversy and lasting arguments between herself and more liberal fans.