The Mike O'Callaghan Professional Papers (1943, 1968-2004) mainly consist of research files gathered by Mike O'Callaghan in his post-political capacity as executive editor of the Las Vegas Sun as well as owner and publisher of the Henderson Home News, Boulder City News, and Green Valley News. The papers also contain handwritten and typewritten drafts of O'Callaghan's "Where I Stand" article for the Las Vegas Sun, along with his reporter's notebooks, monthly planners, and photographic prints. The research files cover a wide variety of topics, including but not limited to environmental issues; nuclear waste; state and local politics; military and veterans affairs; foreign relations including Israel, Iraq, and Korea; and education. The collection also contains copies of speeches given by O'Callaghan as the 23rd Governor of Nevada between 1971 and 1979, some of which contain handwritten notations.

The Howard Hughes Public Relations Photograph Collection depicts the activities of businessman Howard Hughes from 1930 to 1950. The photographs primarily depict aircraft flown by Hughes or designed by the Hughes Aircraft Company, including the XF-11 reconnaissance plane, the HK-1 Hercules (or "Spruce Goose"), and the Hughes H-1 Racer. The photographs also depict celebrations following Hughes's circumnavigation flight in New York City, New York and Chicago, Illinois in 1938. Lastly, the photographs include Hughes testifying in front of the Senate Special Committee to Investigate the National Defense Program in 1947.