The New York State Tenement House Act of 1901 banned the construction of dark, poorly ventilated tenement buildings in the U.S. state of New York. Among other sanctions, the law required that new buildings must be built with outward-facing windows in every room, an open courtyard, proper ventilation systems, indoor toilets, and fire safeguards. One of the reforms of the Progressive Era, it was one of the first laws of its kind in the U.S.

A tenement is a type of building shared by multiple dwellings, typically with flats or apartments on each floor and with shared entrance stairway access. They are common on the British Isles, particularly in Scotland. In the medieval Old Town, in Edinburgh, tenements were developed with each apartment treated as a separate house, built on top of each other. Over hundreds of years, custom grew to become law concerning maintenance and repairs, as first formally discussed in Stair's 1681 writings on Scots property law. In Scotland, these are now governed by the Tenements Act, which replaced the old Law of the Tenement and created a new system of common ownership and procedures concerning repairs and maintenance of tenements. Tenements with one or two room flats provided popular rented accommodation for workers, but in some inner-city areas, overcrowding and maintenance problems led to shanty towns, which have been cleared and redeveloped. In more affluent areas, tenement flats form spacious privately owned houses, some with up to six bedrooms, which continue to be desirable properties.