Dorothy Josephine Baker (September 30, 1915 – May 14, 1973), also known as Big Dorothy, was an American madam in Helena, Montana in the mid-20th century. She ran a brothel officially known as "Dorothy's Rooms" on Last Chance Gulch in Helena from the mid-1950s until it was shut down in a police raid in 1973. While running the brothel, she also donated to many charities, including churches and law enforcement programs, making her generally popular among the local citizens.