Dorothy was born in San Francisco Jan 3, 1897, but grew up in Los Angeles. After graduating from high school, she attended USC towards becoming a medical doctor. During WW I, she left USC to go to Europe to become an ambulance driver. After the war, she returned home, but did not return to college. Dorothy contacted some of the many movie people she knew who used to frequest her families restaurant and got a job at Paramount Studios. The man who got her the job as script writer was director William C. DeMille, older brother of Cecil B. DeMille. Dorothy was later promoted to film editor and her first job was editing the 1922 BLOOD AND SAND starring Rudolph Valentino. In 1927 Arzner threatened to leave Paramount unless she could direct. They put her in charge of FASHIONS FOR WOMEN which was a financial success.
Ms Arzner was an open lesbian, very daring for those times. She often dressed in men's suits and ties, but always wore skirts rather than slacks. Arzner directed Paramount's first talkie in 1929, THE WILD PARTY, which starred Clara Bow, Fredric March, and Jack Oakie. Arzner had technicians rig a microphone into a fishing rod so Clara Bow could move about the set, essentially creating the first boom mike.
Arzner left Paramount in 1932 to work as an independent director and did very well. She was the first woman to join the Directors Guild of America.
She stopped directing feature length files in 1943 and began directing TV commercials and Army training films. She produced plays in the 1960's and 70's, was a professor at UCLA film school, teaching screenwriting and directing until her death in 1979.
Dorothy never married, never had children, and died at age 82. Although she was linked romantically to many actresses, she lived openly with dancer and choreographer Marion Morgan from 1930 until Morgan died in 1971.