Adams entered the diplomatic service of the Holy See on March 8, 1976. He held positions in the office of the Secretary of State and in
Rwanda, Kenya,
Honduras, the Republic of Ireland,
Denmark and the Czech Republic. On September 3, 2007, he was appointed apostolic nuncio to the
Philippines. On February 22, 2011, Adams was appointed papal nuncio to
Greece and on April 8, 2017, he was named to replace Archbishop
Antonio Mennini as
apostolic nuncio to Great Britain. Adams' title refers to "Great Britain" rather than "United Kingdom" because the nuncio has no role in
Northern Ireland, a part of the United Kingdom. The Catholic Church in Northern Ireland is administered locally, with its apostolic nuncio based in Dublin. In February 2019,
the Guardian reported that Adams received repeated requests for information to the
Independent Inquiry into Child Sexual Abuse (ICSA) held by the British Government. Adams did send a response to the
Foreign and Commonwealth Office because he said that was the appropriate channel. On October 5, 2019, an ICSA member was quoted by
The Tablet as saying that the Holy See told ICSA that "the domestic laws and internal proceedings of a foreign sovereign entity are not the proper object for a British inquiry".
Pope Francis accepted Adam's resignation as apostolic nuncio to Great Britain on January 31, 2020. ==Honors==