The story centers on the relationship between Mrs Kitty Warren, a brothel owner, described by the author as "on the whole, a genial and fairly presentable old blackguard of a woman" and her daughter, Vivie, an intelligent and pragmatic young woman, who has just graduated from college and come home to get acquainted with her mother for the first time in her life. The play focuses on the characters' relationships to each other as shaped by Mrs. Warren's choices, and the social hypocrisies relating to prostitution and the limited opportunities available for women in Victorian England. Vivie Warren, an educated, thoroughly modern young woman, has just graduated from college with honors and is available for suitors. Her mother, Mrs. Warren (her name changed to hide her true identity and give the impression that she is married) arranges for her daughter to meet her friend Praed, a young, handsome architect, at her home. Mrs. Warren arrives with her business partner, Sir George Crofts, who is attracted to Vivie regardless of his age difference. Vivie is romantically involved with the youthful Frank Gardner, who sees Vivie as his meal ticket, and whose father, the married Reverend Samuel Gardner, has a history with Vivie's mother and is in fact Vivie's out-of-wedlock father, making Vivie and Frank half-siblings. Mrs. Warren successfully justifies to her daughter why she chose her particular profession (managing a chain of brothels throughout Europe) in order to support her daughter and give her every opportunity she never had. Vivie is at first horrified at the revelation but then lauds her mother as a champion. However, the reconciliation ends when Vivie discovers that her mother continues to run her business even though she no longer needs to. Vivie takes an office job in the city, dumps Frank, vowing she will never marry, and disowns her mother. Mrs. Warren is left heartbroken, having looked forward to growing old with her daughter.

Middle-aged Mrs. Warren is a madam, proprietress of a string of successful brothels. Her daughter, Vivie, is a modern young woman, but not so modern that she's not shocked to discover the source of her mother's wealth. The clash of these two strong-willed, but culturally constrained Victorian women, is the spark that ignites the ironic wit of one of George Bernard Shaw's greatest plays, in a withering critique of male domination, sexual hypocrisy, and societal convention. Initially banned after its 1893 publication due to its startling frankness, Mrs. Warren's Profession remains a powerful work of progressive theater.