[5] One of his major contributions was reformulating the Ricardian idea of comparative advantage in a neoclassical framework, abandoning the labor theory of value for an opportunity cost concept.
He continued his studies in 1923 and began working as a librarian at the chamber for commerce, trade and industry in Vienna in the summer of 1924.
In 1936 he moved to the United States, joining the economics department at Harvard University.
However, when a second report by Prebisch or the United Nations Conference on Trade and Development (UNCTAD) came out in 1964, Haberler denounced it.
In 1971, Haberler left Harvard to become a resident scholar at the American Enterprise Institute.