Smithson was born in Sheffield, South Yorkshire. While studying architecture at Durham University (1939-1942), she met Smithson, who she married in 1949. Together, they joined the architecture department of the London County Council before establishing their own partnership in 1950.
Their style draws heavily on influences from Ludwig Mies van der Rohe, leaning towards minimalism. They were associated Team 10 and its 1953 revolt against old Congrès International d'Architecture Moderne (CIAM) philosophies, arguing instead for 'streets in the sky' where inhabitants could live and work, and with the Independent Group (an off-shoot of the Institute of Contemporary Arts}.
Their projects included:
Alison Smithson died in 1993.