Justice David Unterhalter holds degrees from Trinity College, Cambridge, the University of the Witwatersrand and University College Oxford.

Justice Unterhalter practiced at the Johannesburg Bar 1990 - 2017. Silk was conferred upon him in 2002. He specialised in competition law (and other areas of regulatory law), trade Law, commercial and constitutional Law. In 2009, he was called to the Bar in London and was a tenant at Monckton Chambers. He served on a number of World Trade Organisation panels, and was appointed to the WTO Appellate Body and served as its Chairman. As an advocate, he appeared in Courts and Tribunals in South Africa, Southern Africa and the UK.  He has held appointments on ICC, ICSID, UNCITRAL and domestic arbitration tribunals.

David Unterhalter was a Professor of Law at the University of the Witwatersrand, the Director of the Mandela Institute, and is a Professor of Law in the Faculty of Law at the University of the Cape Town.

 In 2018 he was appointed to the High Court as a judge. He has since been appointed as an acting appeal court judge of the Competition Appeal Court and (from June 2020 ) of the Supreme Court of Appeal.