After completing his PhD from the University of Birmingham, Whittington spent much of his career out of Britain. He started his professional career at the University of Rangoon, Burma. Then he moved to China to teach at Ginling Women's College. After the end of World War II, he moved to Harvard University to become Professor of Palaeontology, and simultaneously Curator of Invertebrate Palaeontology at the Museum of Comparative Zoology. It was during this period that he began his major works in palaeontological research. Towards the last part of his career, he returned to England as Woodwardian Chair in Geology at the Department of Earth Sciences, University of Cambridge and was affiliated to Sidney Sussex College.