Union of Construction, Allied Trades and Technicians or UCATT is the British Trades Union representing workers in the construction and building industry.

It can trace its origins back to the formation of the General Union of Carpenters and Joiners in 1827 which later became known as the Amalgamated Society of Woodworkers; this merged with the Amalgamated Union of Building Trade Workers in 1972 to form UCATT.