Hardy worked as assistant professor of organic chemistry at Bryn Mawr College in 1939 and 1940. In the years 1942–1958, Hardy worked as a chemist at Calco Chemical Division, subsequently she worked as a literature chemist at Lederle Labs from 1958 to 1975. After working for Lederle, Hardy worked as a senior resident literature chemist for American Cyanamid Company from 1975 on. She was a member of the American Association for the Advancement of Science, American Chemical Society and Chemical Institute of Canada. Hardy worked in a number of different research areas including molecular rearrangements, preparation of unsaturated esters and ketones, vat dyestuffs, esterification of leuco vat dyes, organosulfur compounds, and pharmaceutical chemistry.