The county council consisted of elected councillors and co-opted county aldermen. The entire body of county councillors was elected every three years. Aldermen were additional members, there being a ratio of one alderman to three councillors. Aldermen had a six-year term of office, and one half of their number were elected by the councillors immediately after the triennial elections.

The first elections were held in January 1889. The first meeting of the "provisional" county council was held on 14 February 1889 at Westminster Town Hall. Although the council did not use political labels, among the aldermen elected were members of the parliamentary Conservative Party.

From 1919, the scarcely political composition of the council was challenged by the election of members of the Labour Party.^[1] The 1922 and 1925 elections were, for the most part, not run on party lines.^[2] In 1928, the majority of the council were described as "Moderate", with Labour forming an opposition.^[3] Labour continued to make advances at the 1931 election, and this led to the formation of a Middlesex Municipal Association "representative of all anti-Socialist members". The association was supported by the various Conservative Party organisations of the county although it was not officially affiliated to the party, and controlled the council until 1946.^[4]

In 1946, Labour took control of the county council for the first time. Following this, the Conservative Party contested elections to the county council, winning control in 1949 and holding it at the 1952 and 1955 elections.^[5][6] In 1958 Labour regained control.^[7] At the elections held in 1961, the Conservatives were returned to power.^[8] These were to be the final elections to the county council: under the London Government Act 1963 the elections due in 1964 were cancelled, with the elections to the shadow Greater London Council being held instead.

The chairman of the county council chaired its meetings and also represented it in a ceremonial manner, in a similar fashion to the mayor of a borough. Twenty-nine people served as chairmen over the council's existence.^[9]

Middlesex County Council's main responsibilities were:^[19]

• Highways and bridges: including the construction or widening of the Great West Road, Western Avenue, North Circular Road Great Cambridge Road and the Chiswick Flyover. A joint committee with Surrey County Council had responsibility for bridges over the Thames. Among bridges constructed or reconstructed were Kew Bridge, Hampton Court Bridge, Twickenham Bridge and Chiswick Bridge.
• Education: In 1891 the county council began providing technical education. In 1902 it was given responsibility for secondary education throughout the county and for primary education in some areas. Under the Education Act 1944 it became the education authority for all purposes. At the time of its abolition, Middlesex County Council maintained 622 primary schools, 232 secondary schools, 12 nursery schools and 29 special schools. There were 14 technical colleges, colleges of art or commerce and two teacher training colleges. The technical colleges were the forerunners of the present University of Middlesex and Brunel University London.
• County Library Service
• Public Hospital Service: following the abolition of the poor law system in 1930, the county council took over a number of hospitals. Examples were Chase Farm Hospital, the North Middlesex Hospital and Edgware General Hospital. These passed to the National Health Service in 1948.
• Middlesex Fire Service from 1948.
• Middlesex Ambulance Service from 1948.
• Main drainage and sewage disposal.
• Motor taxation from 1909.
• Planning from 1948.
• Various regulatory and licensing functions includes weights and measures.
• The division of the county into coroner's districts and the appointment of coroners.

The principal officers of the county council over its 76 year existence were:^[20]

Clerk of the County Council edit

• 1889-1909: Sir Richard Nicholson
• 1909-18: Walter George Austin
• 1919-35: Ernest Walter Sidney Hart (knighted 1935)
• 1935-54: Clifford Walter Radcliffe (knighted 1953)
• 1955-65: Kenneth Goodacre - became Deputy Clerk of the Greater London Council 1964.

County Engineer and Surveyor edit

• 1889-98: Frederick Hyde Pownall
• 1898-1920: Henry Titus Wakelam
• 1920-32: Alfred Dryland
• 1932-49: William Henry Morgan
• 1949-65: Henry Stuart Andrew

Chief Education Officer edit

• 1945-52: Thomas Benjamin Wheeler
• 1952-65: Cecil Ernest Gurr

Chief Officer of Fire and Ambulance Service / Chief Fire Officer edit

• 1948-63: Alfred Wooder
• 1963-65: Frank Stephen Mummery

The number of homes in Middlesex, an area static in size, rose from 236,266 to 665,347 in the forty years to 1961.^[21] The chart of this rise, which tapered off, shows that by 1951 Middlesex formed part of the London conurbation, and in 1965 the council was abolished on the creation of the Greater London Council. All but four electoral divisions of the council's closing 87 became part of the brand-new Greater London; the rest were transferred to Surrey as to the two parts of Staines plus Sunbury-on-Thames, or to Hertfordshire as to Potters Bar. These were three urban districts.