Florence Ryerson (September 20, 1892 – June 8, 1965) was an American playwright, screenwriter and co-author of the script for the 1939 film "The Wizard of Oz." Between 1915 and 1927 she published more than 30 short stories and then joined Metro-Goldwyn-Mayer in 1926 to work on silent film scripts. In 1930 and 1933 she and her husband wrote two of the earliest books about teenage girlhood. The books were based on a short story series Ryerson had started in 1925. She continued to write for most of her life, writing plays for Broadway in the 1940s.