Willem is the founder of Otterspeer, Haasnoot & Partners (OHP) and a highly experienced Dutch tax advisor. He assists multinational companies and private clients with Dutch and international tax matters, with a focus on cross-border structuring, repatriation planning and international M&A.

Willem has extensive experience advising on complex transactions and reorganisations, including acquisition and disposal structuring, transaction documentation and post-deal implementation. In addition, he supports clients in Dutch tax audit processes and helps prevent and resolve cross-border tax disputes by aligning tax positions with business reality and ensuring robust documentation and stakeholder alignment.

Willem studied Dutch Law and Tax Law and completed the NIVRA programme. He is also a Chartered Accountant. Earlier in his career, he worked as a Dutch tax inspector. Before founding OHP, he was a tax partner at a Dutch Big Four firm.