Zetterberg graduated with a degree in business. After starting his career in the Swedish paper industry, he became CEO of the state-owned PK-Banken (now a part of Nordea) in 1988. As such he took part in buying Carnegie from Erik Penser. In 1990 he moved to one of the most prestigious jobs in Swedish industry at that time – CEO of Volvo. He stayed in that position for two years, serving under Chairman Pehr G. Gyllenhammar. After leaving Volvo in 1992, Zetterberg served on a number of different boards.