In 1997 he was appointed a judge of the
Labour Court, and in 1999 he was appointed to the
Transvaal Provincial Division of the
High Court (later the North Gauteng High Court, now the
Gauteng Division). In 2000 he was elevated to Judge President of the Labour Court, In 2010 he returned to the Pretoria High Court. From November 2011 to May 2012, Zondo served as an acting judge of the Constitutional Court. He was permanently appointed with effect from September 2012 and is now considered a key member, with
Chris Jafta, of the Court's conservative wing. In June 2017, President Jacob Zuma appointed Zondo to the office of Deputy Chief Justice, succeeding Dikgang Moseneke who retired in 2016. On 10 March 2022, President
Cyril Ramaphosa appointed Zondo as the new Chief Justice of the Constitutional Court of South Africa, effective 1 April. ==Commission of Inquiry into State Capture==