Edward Stratemeyer, the founder of the Syndicate, hired writers, beginning with Mildred Wirt, later Mildred Wirt Benson, to write the manuscripts for the Nancy Drew books. The writers initially were paid $125 for each book and were required by their contract to give up all rights to the work and to maintain confidentiality.

Benson and Harriet Adams (Stratemeyer's daughter) are often credited as the primary writers of Nancy Drew books under the pseudonym Carolyn Keene; other ghostwriters who used this name to write Nancy Drew mysteries included James Duncan Lawrence, Walter Karig, Nancy Axelrad, Priscilla Doll, Charles Strong, Alma Sasse, Wilhelmina Rankin, George Waller Jr., Margaret Scherf, and Susan Wittig Albert. Also involved in the Nancy Drew writing process were Harriet Stratemeyer Adams's daughters, who gave input on the series and sometimes helped to choose book titles; the Syndicate's secretary, Harriet Otis Smith, who invented the characters of Nancy's friends Bess and George; and the editors at publishers Grosset and Dunlap. The editors at Grosset and Dunlap were so heavily involved in writing the Drew books that they won the rights to the first 56 titles as the result of a 1980 lawsuit.

In 1986, the Syndicate was bought by publishers Simon & Schuster; the Drew books are now handled by Mega-Books, a New York book packager.

Leslie McFarlane wrote the first four Dana Girls stories in 1934 and 1936. This series is a feminized version of The Hardy Boys. These volumes were advertised as being written by the author of Nancy Drew, and were promoted heavily on dust jackets for this series. The Dana Girls were later ghostwritten by others, including Mildred Benson and Harriet Adams. The series went out of print for about four years, from 1945 to 1949, and was reintroduced with revised dust jacket art and illustrations at that time. The series stopped production in 1968, was modernized, and reintroduced in 1972.