Scott Hamilton was appointed Head of the International Office in February 1980, at the same time as the International Office was merged with the Conservative Research Department. Consequently, he was also made Head of Foreign Affairs Section within CRD, where he had previously worked as a desk officer. As of 1981, his responsibilities within the International Office were:

In July 1983, Hamilton was also formally appointed Secretary General of the International Democrat Union, which took up half of his time. Consequently, the decision made in 1980 to merge the roles of Head of the International Office and Head of Foreign Affairs Section of CRD was reversed. Hamilton continued jointly as Head of the International Office and Secretary General of the IDU until 1989.