Loopbaan Willem Horstmann
- 2022 - 2023 Commissaris, Triodos Bank
- 2016 - 2022 CRO (Chief Risk Officer), Aegon Nederland
- 2017 - 2021 Commissaris, Aegon Bank
- 2014 - 2015 CRO (Chief Risk Officer), VIVAT Verzekeringen
- 2010 - 2014 CFRO, Zwitserleven
- 2007 - 2010 Director, Aegon Corporate & Institutional Clients
- 2004 - 2007 Finance and product development director, Aegon Corporate & Institutional Clients