This article discusses some of the factors that will affect house building in England and Wales during the next twenty years. It is hardly possible to predict the demand for new houses, as it is for consumer durables like cars and domestic appliances, by reference to changes in incomes and prices. Governments in Britain (as in most other wealthy countries) have taken the view that housing is, up to a point, a social responsibility and should not be left to the free play of market forces. Private rents have been controlled; most of the new houses since the war have been built by local authorities to be let at subsidised rents; and certain minimum standards have been laid down both for new public housing and for existing privately owned houses. Hence the cost of housing to the occupier, and the supply of new houses, have been largely dominated, directly or indirectly, by public policy; and the size of the house building programme is likely to continue to be, at least partly, a political decision.