Campbell joined the
Foreign and Commonwealth Office in 1982 and started in the North America Department. In 1984, he moved to the
Secretary of State's Private Office and the next year was placed to the UK Embassy in
Khartoum as an economist. From 1988 he worked at the embassy in
Dhaka and from 1992 at the embassy in
Jakarta. Campbell served as the
Ambassador to Nicaragua from 2011 to 2015. Because the UK did not have an embassy in Nicaragua, the post was non-residential and Campbell worked from
San José. On 13 October 2020, he was recognised as British Ambassador to Ecuador. Campbell served as ambassador until August 2025, with Libby Green being announced as his successor. ==Personal life==