From 2006 until 2014, Jack was Vice Chairman of the Supervisory Board of Evides. Prior to that, from 1986 to 2003, Jack worked for PricewaterhouseCoopers NV, where he fulfilled various management functions and was appointed Senior Partner in 1990 and Managing Partner & Territory Leader in 1998, responsible for the Transaction Services practice in the Netherlands. He was employed with the Dutch Ministry of Finance from 1980 to 1986. Since 2011, Jack is a member of the Supervisory Board of Corbion NV and became Chairman of the Audit Committee of Corbion NV as per 1 January 2016. He also serves as a member of the Advisory Council YGroup Companies and became a member of the Supervisory Board of Royal Boskalis in May 2018.
Jack was first appointed to the TomTom Supervisory Board in January 2017. His current term runs until 2021.