Duncan Pieterse serves as Director-General of the National Treasury of South Africa, where he has worked for the last ten years, including as Deputy-Director General of Asset and Liability Management and Deputy-Director General of Economic Policy. He is also an Adjunct Associate Professor in the School of Economics at the University of Cape Town. He has worked as a development economist and public finance consultant in South Africa and has spent time at Yale and Brown Universities in the United States as a research fellow.

He has Doctorate, Master and Bachelor of Business Science degrees in economics from the University of Cape Town and a Master in Public Administration from Harvard University.