After the 1972 general election Pronk was appointed as Minister for Development Cooperation in the Den Uyl cabinet taking office on 11 May 1973.

In July 1980 Pronk was nominated as Assistant Secretary-General of the United Nations Conference on Trade and Development (UNCTAD) taking office on 18 August 1980.

After the 1989 general election Pronk was again appointed as Minister for Development Cooperation in the Lubbers III cabinet taking office on 7 November 1989.

After 1998 general election Pronk was appointed as Minister of Housing, Spatial Planning and the Environment in the Kok II cabinet taking office on 3 August 1998.

In June 2004 Pronk was nominated as the first Special Representative of the United Nations in Sudan serving 1 July 2004 until 10 December 2006.

Following his retirement Pronk continued to be active as an advocate and activist for human rights, the anti-war movement, social justice and for more European integration.

He attended the Protestant secondary school Zandvliet Lyceum in The Hague, where he graduated the gymnasium in 1958 with a curriculum that focused on exact sciences.

[1] As a student, he worked as a guide on the Henri Dunant, the Dutch Red Cross's holiday ship for the disabled.

[1] He changed the development cooperation policy of the Netherlands, giving it a political goal: the equal distribution of power and wealth in the world.

[1] His left-wing policy put him at odds with the more moderate PvdA Minister of Foreign Affairs Max van der Stoel.

[1] As Minister for Development Cooperation, Pronk held several prominent positions in international organizations: between 1973 and 1977 he was Deputy Governor of the World Bank.

He combined this period in Parliament with several posts in the world of development cooperation: in 1979 he also became Professor of International Development at the Institute of Social Studies; he was a member of the committee "Church Participation in Development" of the World Council of Churches and of the Councils Commission of Advisors on Economic Affairs; he was a member of the International Commission for the Study of Communication Problems of UNESCO; and in the Netherlands he was member of the Council for Government and Social Affairs of the Dutch Reformed Church.

[1] In 1989 he combined his work as MP with a position as professor at the University of Amsterdam, where he occupied the "Joop den Uyl chair", created by the scientific foundation of the PvdA.

In 1992 his criticism of Indonesian government's record on human rights, caused the Indonesian government to refuse development aid from the Netherlands and to conclude the long-standing international aid coordination arrangements, chaired by the Netherlands, which had been maintained since the late 1960 through the Inter-Governmental Group on Indonesia.

[1] In 2000 and 2001 he chaired the UN climate conference, where parties agreed upon a compliance mechanism for the Kyoto protocol for the reduction of greenhouse gases.

In June 2004 Pronk was appointed UN Special Representative for Sudan by United Nations Secretary-General Kofi Annan On September 21, 2006, Pronk asked the warring parties in Darfur, including President Omar al-Bashir and the seven rebel movements, to observe a "month of tranquility" during Ramadan, which would begin September 23, 2006.

His implicit call for a ceasefire in the western region of Sudan came after the Khartoum government withdrew its ultimatum for African Union peacekeepers to pull out.

In addition the rejectionist factions should end the quarrel to start talking about everything related to the Darfur peace agreement to improve it.

[8] On October 27 the UN Security Council and UN Secretary General Kofi Annan announce that Pronk will serve out his last months as Special Representative of the Secretary-general in Sudan.

[9] Pronk's story roughly parallels that of Mukesh Kapila, a previous UN employee who was forced to leave Sudan after making critical comments about the Darfur conflict.