Few apartments had bathrooms before the turn of the century, and the idea that a toilet in each apartment was not a luxury became accepted only slowly. Well into the twentieth century, the actual conditions in these overcrowded dwellings were clearly unhealthful, although improved water and sewer systems had already made an enormous difference even before 1900. After World War II, in a time of reduced population and greater prosperity, housing densities declined and the same buildings gradually acquired a new reputation.
