Della Street was the fictional secretary of Perry Mason in the long-running series of novels, short stories, films, and radio and television programs featuring the fictional defense attorney created by Erle Stanley Gardner.
In the first Perry Mason novel, The Case of the Velvet Claws, written in the early days of the Great Depression, Della Street is revealed to have come from a wealthy, or at least well-to-do, family that was wiped out by the stock market crash of 1929. Della was forced to get a job as a secretary. By the time of the TV series in the 1950s and 1960s, this would have not fit well with the age of the characters as then portrayed. According to The Case of The Caretaker's Cat, she is about 15 years younger than Perry Mason.
A character named Della Street first appeared in Gardner's unpublished novel Reasonable Doubt, where she was a secretary, but not the secretary of the lawyer, Ed Stark. Gardner described her this way: "Della Street … Secretary, twenty-seven, quiet, fast as hell on her feet, had been places. Worked in a carnival or side show, knows all the lines, hard-boiled exterior, quietly efficient, puzzled over the lawyer, chestnut hair, trim figure, some lines on her face, a hint of weariness at the corners of her eyes." When Gardner submitted Reasonable Doubt to William Morrow, an editor suggested that "Della Street is a better character than the secretary." Gardner took this suggestion when he rewrote Reasonable Doubt as The Case of the Velvet Claws and made Della Street Perry Mason's secretary. In the published novel, the carnival or side show was jettisoned, and Street came from a more respectable background. This is a good example of the difference between the pulp writing and slick writing of the 1930s.
In 1950, Gardner published the short story "The Case of the Suspect Sweethearts" under the pseudonym Della Street.
Several instances of sexual tension are seen between Mason and Street in the Gardner novels, multiple glances, kisses, and so on, and several proposals of marriage, all of which Della turned down because she wanted to be a part of Mason's life and she knew that meant being a part of his work.
Erle Stanley Gardner, the creator of Perry Mason in a series of novels, was a very prolific author, who employed three secretaries simultaneously, all sisters, to keep up with his output. One of them he eventually married, after his first wife—from whom he was separated for 30 years—died. This was Jean Gardner, born Agnes Helene Walter. People who knew her believed she was the inspiration for Della Street, though neither she nor Gardner himself admitted it. Mrs. Gardner said she thought he put several women together to create the character.
In the film adaptations made in the 1930s, Della Street was portrayed by five different actresses: Helen Trenholme, Claire Dodd, Genevieve Tobin, June Travis, and Ann Dvorak.
On television, Della Street was played by Barbara Hale in the series, for which she received an Emmy Award, and in the 30 made-for-TV movies. Sharon Acker played Della Street in the short-lived revival series The New Perry Mason, starring Monte Markham as Mason.
Gertrude Warner was the first actress to portray Street regularly, albeit on the radio series, followed by Joan Alexander and Palmolive's "Madge", Jan Miner. The character portrayed in the radio series was reworked into Sara Lane on the daytime show Edge of Night, which was to be the daytime Perry Mason, until Gardner pulled his support for the project.