The Metropolitan Boroughs of St. Pancras, Holborn and Hampstead merged to become Camden in 1965. Under the stewardship of Sydney Cook, the new borough quickly became renowned for its radical new housing. Cook appointed a "dream team" of architects working out of Holborn Town Hall, led by Neave Brown. George Benson and Alan Forsyth joined the department in 1968, directly from the Architectural Association, and teamed up with Brown to design the famous Alexandra Road development.

Recognising the talent of these two young architects, Cook gave Benson and Forsyth the Mansfield Road project. The scheme consisted of 73 flats (as well as 9 family houses on Lamble Street) constructed between 1974 and 1980. The new buildings replaced a terrace of 19th-century houses, and were built as part of a more widespread renewal of the locality known as the Gospel Oak Redevelopment Area.

The street frontage borrows stylistically from Neave Brown's houses at Winscombe Street (which were taken as the starting point for much of what the Camden architects built at this time), with similar window patterns and spiral staircases.

The terrace is sunk below street level to match the houses behind. The flats have a split-level cross section, which creates exciting inter-connecting spaces that appear bigger than they are. Natural light is brought in through conservatory-style sloping glazed ceilings, and skylights in the bathrooms.

According to the Twentieth Century Society, "The development was neither cheap nor easy to build, and to obtain a tender list Camden had to approach sixty contractors. It took six years and a tower crane was needed – exceptional for three-storey housing on this scale. But worth it."