Designated new towns were removed from local authority control and placed under the supervision of a development corporation. These corporations were later disbanded and their assets split between local authorities and, in England, the Commission for New Towns (later English Partnerships).
The first wave was intended to help alleviate the housing shortages following the Second World War, beyond the green belt around London. A couple of sites in County Durham were also designated. These designations were made under the New Towns Act 1946.
The second wave (1961–64) was likewise initiated to alleviate housing shortfalls. Two of the locations below (Redditch and Dawley New Town — later renamed Telford) are situated near the West Midlands conurbation; another two (Runcorn and Skelmersdale) are near Merseyside and were intended as overspill for the city of Liverpool.
The third and last wave of new towns (1967–70) allowed for additional growth chiefly further north from the previous London new towns, with a few developments between Liverpool and Manchester, namely "Central Lancashire" and Warrington. Dawley New Town was redesignated as Telford New Town, with a much larger area, as overspill for Birmingham and nearby towns including Wolverhampton. About halfway between Birmingham and London was the new town of Milton Keynes (which took its name from a village in the area, but also swallowed up existing towns Newport Pagnell and Bletchley), while nearer to Birmingham, the existing town of Northampton was expanded. In East Anglia, the existing town of Peterborough was designated as a new town to accommodate overspill from London.