 He started working in the New Zealand Customs Department in 1929, before moving to the Prime Minister's Department in the fledgling Foreign Ministry.In 1940, Laking became head of the Organisation for National Security, managing the War Cabinet Secretariat, a post he held until 1948.In 1949, Laking was appointed Minister to the New Zealand Embassy in Washington, serving as deputy to Ambassador Carl Berendsen, for seven years.