Kenneth F. Hackett officially became the new US ambassador to the Holy See after presenting his credentials to Pope Francis on 21 October.
Ambassador Hackett has a four decade-long association with the Catholic Relief Services (CRS), a large international development agency, which he served as president for 18 years.
He was also a member of the Pontifical Council for charitable works Cor Unum from 1994 until 2012, before being nominated by US president Barack Obama to his current role in June this year.
The ambassador, who is joined in Rome by his wife Joan, has launched a blog where he will share his experiences as US ambassador to the Vatican.
Prior to Hackett's arrival there was no US ambassador to the Vatican since Miguel H. Diaz resigned last November to take up a teaching position at the University of Dayton in Ohio.