Although the McMillan Plan resulted in the demolition of some slums in the Federal Triangle area, substandard housing was a much larger problem in the city during the early 1900s, with large portions of the population living in so-called "alley dwellings." Progressive efforts eventually led to the creation of the Alley Dwelling Authority in 1934. The agency, led by John Ihlder, was an early example of a public housing agency, and was responsible for demolishing slum housing and building new units that were affordable, modern, and sanitary.