Arthur Chaskalson was appointed by President Nelson Mandela in June 1994 to be the first President of South Africa's new Constitutional Court and was the Chief Justice of South Africa from November 2001 until his retirement in 2005.

He was a consultant to the Namibian Constituent Assembly in connection with the drafting of the Constitution of Namibia (December 1989-March 1990), a Consultant to the African National Congress on constitutional issues (April 1990-April 1994), and served as a member of the Technical Committee on Constitutional Issues, appointed by the Multi Party Negotiating Forum in May 1993 to give advice on constitutional matters to the Forum (which negotiated the transition to democracy in South Africa), and to draft on its behalf the transitional constitution, which was finalised and adopted in December 1993.

From 1978-1993 he was the Director of the Legal Resources Centre, and was the leading counsel in several cases in which challenges were launched by the LRC against the implementation of apartheid laws. He also appeared as counsel on behalf of members of the liberation movements in several major political trials between 1960 and 1994, including the Rivonia Trial in 1963/1964 at which Mr. Nelson Mandela and other leaders of the African National Congress were convicted and sentenced to life imprisonment

He was the President of the International Commission of Jurists, the Chairperson of a committee of senior judges appointed by the United Nations Environmental Programme to promote and develop judicial education on environmental law in all parts of the world, the first chairperson of the Southern African Judges Commission, an association of the Chief Justices of Southern Africa, and chaired the Eminent Jurists Panel appointed by the International Commission of Jurists to enquire into the impact of terrorism and counter-terrorism on the rule of law, human rights law, and where relevant, international humanitarian law.

He has received numerous awards for his work in promoting human rights, is the recipient of 9 honorary doctorates, and the award of Supreme Counselor of the Baobab [gold], a national honour, for his service to the nation in respect of constitutionalism, human rights and democracy. On his retirement in 2005 he was described by the President as a “giant among the architects of our democracy”.