He was briefly his country's Deputy Permanent Representative to the United Nations in 1972, then served as Ambassador to Venezuela (with additional accreditation for Colombia, Ecuador, and Peru) from 1972 to 1978.

[1] Subsequently, having returned to Guyana, Insanally was Head of the Political Division covering the Western Hemisphere, also serving as Ambassador to Colombia and as High Commissioner to a number of Caribbean nations.

[2] At the UN, he was vice-president of the United Nations Council for Namibia prior to Namibian independence in 1990, and in April 1990 he was Vice-president/Rapporteur of the Special Session of the General Assembly on International Economic Cooperation.

He also served as Chairman of the Open Ended Working Group on the question of Equitable Representation on and increase of the Membership of the Security Council.

During this period, he was also a member of the Board of - Governors of the Institute of International Relations, St. Augustine, Trinidad and Tobago.