After dropping out of college, Duncan continued to write and publish magazine articles; she wrote over 300 articles published in magazines such as Ladies' Home Journal, Redbook, McCall's, Good Housekeeping, and Reader's Digest.
She published her first novel, Love Song for Joyce, in 1958 under the pen name Lois Kerry, followed by Debutante Hill in 1959; the latter was initially rejected for a literary prize because it featured an adolescent character drinking a beer.

In 1962, Duncan moved to Albuquerque, New Mexico with her children after divorcing her first husband, Joseph Cardozo, and supported herself writing greeting cards and fictional confessionals for pulp magazines.
In 1966 she published the novel Ransom, detailing a group of students held captive on a school bus, which earned her an Edgar Allan Poe Award nomination, as well as marking her shift from romance to more suspense-oriented works.

In the early 1970s, Duncan was hired to teach journalism at the University of New Mexico. "
I was hired on a fluke," Duncan recalled in a 2011 interview: Her friend, who was the chair of the journalism department, hired her as a replacement based on her experience writing for magazines, despite the fact that she did not have a degree.
While teaching, Duncan enrolled in classes at the university, earning her B.A. in English in 1977.

In 1970, she published the historical novel Peggy, chronicling the life of Peggy Shippen, followed by the 1971 children's book Hotel for Dogs, which was later adapted as a 2009 film of the same name starring Emma Roberts.
After dropping out of college, Duncan continued to write and publish magazine articles; she wrote over 300 articles published in magazines such as Ladies' Home Journal, Redbook, McCall's, Good Housekeeping, and Reader's Digest. She published her first novel, Love Song for Joyce, in 1958 under the pen name Lois Kerry, followed by Debutante Hill in 1959; the latter was initially rejected for a literary prize because it featured an adolescent character drinking a beer.
In 1962, Duncan moved to Albuquerque, New Mexico with her children after divorcing her first husband, Joseph Cardozo, and supported herself writing greeting cards and fictional confessionals for pulp magazines. In 1966 she published the novel Ransom, detailing a group of students held captive on a school bus, which earned her an Edgar Allan Poe Award nomination, as well as marking her shift from romance to more suspense-oriented works.
In the early 1970s, Duncan was hired to teach journalism at the University of New Mexico. "I was hired on a fluke," Duncan recalled in a 2011 interview: Her friend, who was the chair of the journalism department, hired her as a replacement based on her experience writing for magazines, despite the fact that she did not have a degree. While teaching, Duncan enrolled in classes at the university, earning her B.A. in English in 1977.
In 1970, she published the historical novel Peggy, chronicling the life of Peggy Shippen, followed by the 1971 children's book Hotel for Dogs, which was later adapted as a 2009 film of the same name starring Emma Roberts.
Lois Duncan