[6] It was his MIT thesis, entitled "The Two - Gap Analysis: A Proposal for North - South Cooperation" that got him recruited to the UN, and it formed the basis of the negotiations for the United Nations Conference on Trade and Development (UNCTAD).

From 1974 until 1980, Arsenis also served as an independent expert with UNCTAD, providing consultancy to the Ministerial Committee of Twenty on the Reform of the International Monetary System..[7] While serving as Director of UNCTAD, Arsenis contributed to the development of numerous proposals – including the creation of special drawing rights (SDR), developmental assistance and coordination of program assistance for the World Bank and the generation of balance-of-payments financing that the IMF subsequently used for effective stabilization and development support schemes.

[6] Gerasimos Arsenis also served as President of the Athens Development and Governance Institute (ADGI-INERPOST), and vice-president of the Marangopoulos Foundation for Human Rights.

[9] Arsenis was a prominent member of the Panhellenic Socialist Movement (PASOK), and his first governmental appointment was as Governor of the Bank of Greece in November 1981, a post he held until February 1984.

[16][17] The following year, he published a book entitled Political Testimony in which he detailed his experiences in office, and accused the Prime Minister of being personally responsible for the failure of reforms.

[16] In April 1987, he announced the formation of the Democratic Initiative party, which he intended to attract other dissilluisioned PASOK members, as well as independents on the left.

[25] In 1996, as part of the Costas Simitis administration, Arsenis was appointed as Minister of National Education and Religious Affairs,[11] a position that he held until 2000.

[1] Gerasimos Arsenis faced significant opposition for the educational system changes he proposed, including widespread demonstrations and strikes.