During his career, he served as the New Zealand high commissioner to Australia, Canada and Malaysia, and ambassador to West Germany.
He was educated at Timaru Boys' High School, and then served in the Royal New Zealand Air Force as a meteorologist from 1942 to 1946.
[1] He graduated from Victoria University College with a Master of Arts degree with first-class honours in 1950.
[1][2] Shepherd joined the Department of External Affairs and became a career diplomat, beginning in 1951 as the second secretary at the New Zealand High Commission in Australia, holding the role until 1954.
Then he was first secretary and deputy head of mission at the New Zealand Commission in South East Asia, stationed in Singapore from 1955 to 1958.