The dissertation is a close examination of the changes and continuities in law applied to prostitutes, bawdy houses, and the application of state police power by cities to segregate both into municipal vice districts. Throughout American history, moral reformers and social commentators recognized prostitution as a social, moral, and urban problem. The debate over the best policy to deal with prostitution was never louder than in the Progressive Era when states passed red-light abatement acts, when newspapers reported on white slavery, when purity crusaders were in full voice, and when cities shut down their vice districts. But prostitution as a criminal offense within the legal context of the courts and the legal traditions of American law has not been explored. If a moral reform group hired a lawyer to do something about a local prostitution problem, the lawyer would find actions in criminal law against prostitution and the keeping of disorderly and bawdy houses and he would find actions in equity to stop and prevent the immoral use of property for disorderly and bawdy purposes. And how did the red-light abatement acts change the law's procedures and standards against bawdy houses and how effective were the acts in closing bawdy houses, vice districts, or stopping prostitution? Furthermore, the turn-of-the-century lawyer might have found himself confronted with a city's policy of districting its bawdy houses and prostitutes into a specific area of the city. The seven chapters of the dissertation begin with a review of some of the writings on prostitution control in the nineteenth and early twentieth century. Then the prostitute-as-vagrant, the theory used against prostitution, is examined. Disorderly houses--the property used for an immoral purpose--provides the focus for chapter three while how the courts actually dealt with disorderly house cases is reviewed in the fourth chapter. Municipalities using state police power to district their immoral houses and women, especially St. Louis and New Orleans, is considered in the fifth chapter, with Houston's decision to district its houses (and to later segregate by race those houses) provides the topic for chapter six. In 1917, Houston closed its vice district and chapter seven covers the reasons for the closing and the events leading to the shutting off the red-lights in Houston.