Adams has been in diplomatic postings overseas in Saudi Arabia, France, South Africa and Egypt.

He was the British Consul-General in Jerusalem from 2001 to 2003, responsible for Britain's relations with the Palestinian people, before joining Jack Straw's private office as Principal Private Secretary to the Foreign Secretary.

He served as Ambassador to Iran 2006–09 and Director-General, Political at the Foreign and Commonwealth Office (FCO) 2009–12.

[2] In September 2013 he took up the post of Ambassador to the Netherlands, and concurrently Permanent Representative to the Organisation for the Prohibition of Chemical Weapons which is based in The Hague.

In January 2017 the FCO announced that he was to transfer to another Diplomatic Service appointment.