Reginald Douglas Crook, 1st Baron Crook (2 March 1901 – 10 March 1989), was a British civil servant and United Nations official.
A member of the Labour Party, he became a senior civil servant.
In 1947 he was raised to the peerage as Baron Crook, of Carshalton in the County of Surrey.
[1] Lord Crook married Ida Gertrude, daughter of Joseph Haddon, in 1922.
Lord Crook died in March 1989, aged 88, and was succeeded in the barony by his only son Douglas.