[4] It was designed by Charles Holloway James and Stephen Rowland Pierce in the Neo-Georgian style with Scandinavian elements,[5] built by C. Miskin & Son of St Albans and opened without ceremony in summer 1939.

[6] The design for the building involved an asymmetrical main frontage facing the Bullocks Lane; the left section of three bays featured a portico with four full height piers supporting a frieze with the words "Tertium iam annum regnante Georgio VI haec curia aedificata est" ("This building was constructed during the third year of the reign of George VI"); the portico contained a doorway flanked by square windows on the ground floor and it contained tall sash windows in a recess on the first floor; there was a copper-clad cupola at roof level; the right section contained a loggia of eleven bays on the ground floor and seven sash windows on the first floor.

[1] The principal room was the council chamber which was contained in a curved structure which jutted out of the main building to the west.

[9] Sculptures of two deer designed by Stephen Elson were erected outside County Hall, to celebrate the fiftieth anniversary of the building, in 1989.

[10] Works of art in County Hall include a portrait of the Lord Chancellor, John Somers, 1st Baron Somers, by Godfrey Kneller[11] and a portrait of the local member of parliament, William Plumer, by Thomas Lawrence.