[1][2][3] A "documentalist",[4] she was particularly known for her work in thesaurus construction and machine-aided indexing,[5] innovating techniques for punch card information retrieval.

While working as a librarian at the Merck, Sharp and Dohme[6] chemical company she "developed a machine-sorted card system that employed Boolean retrieval logic.

[4]: 4 At age 16, she completed high school and attended Juniata College, receiving a four-year scholarship for tuition, and working for a German family for room and board.

[4]: 4–5 Claire wanted to become a doctor, and applied at the Woman’s Medical College of Pennsylvania, but was initially refused because of her age.

She spent the next year working as an attendant at the Philadelphia State Hospital at Byberry as part of a Quaker program for the humane treatment of mental patients.

[4]: 12–13  During much of their marriage, Claire was the primary breadwinner for the family, while Wallace took responsibility for parenting and running their home.

Initially hired as a librarian, she soon became a laboratory assistant to Dr. Edmond J. Farris, studying human reproduction and fertility.

Influenced by Mooers' ideas, Schultz compiled a "subject dictionary" to index the terminology used in scientific journals and by the Sharp and Dohme scientists.

Then they convinced the company that the IBM 101 (which in 1950 was used only at the Census Bureau) could be adapted to do punch card searches with "and, or, and not" connectives, and arranged to rent one.

John Mauchly sought her out at a conference, and after visiting Merck for a demonstration of her use of the IBM, offered her a job whenever she wanted one.

[3] Having experienced the beginning of the information age, Schultz's perspective on the advent of the Internet was that it presented "a huge, formless haystack in which to find needles", which would make "for some very complex mixing and matching" in database searches.