The William Andrew Archer papers (ca.1906–[1929–1964]–1972), HI Archives collection no. 3, consists of seventeen boxes of materials and four bound volumes. The majority of the collection includes reports, printed and mimeographed items, certificates and correspondence. Archer's publications and the published materials of fellow botanists, such as a listing of botanical paintings and drawings by Helen Joslin, are also available throughout the collection.

Much of the collection concerns Archer's international influence as head of the Department of Botany and Plant Pathology at the Escuela de Agricultura, as botanist at the Instituto Agronômico del Norte and as a plant explorer within the Amazon and the Colombian jungles. These explorations and occupations led to publications, reports and photographs that are included within the collection. Specifically, during his exploration of fish poison plants and economic plants in British Guiana, Suriname, Colombia, Mexico, Brazil, Paraguay, Ethiopia and other areas, Archer produced photographs that can be appreciated by users of the collection at the Hunt Institute.

Archer's collection also encompasses materials relating to his more domestic occupations. These resources focus on the topics of his curatorial career within the National Arboretum Herbarium, his years of volunteering with the Smithsonian Institution archives, and his work with the Nevada Indian Medicine Project. The Hunt Institute holds four bound volumes related to the project, which include data and correspondence from the Native American informants, the University of Nevada, the Works Projects Administration and the University of Minnesota that code and identify the native plants that were thought to have medicinal properties. Volume 4 offers a compilation of data that was received from the chemical and pharmaceutical studies that were performed on these plants.

The William Andrew Archer papers were processed and described in 2014 by Abigail Kirstein.