Theo's longstanding affair with association management kicked-off in 1992 when he started working for the RAI Association in the automotive industry. During his 14 years there, he studied association management and climbed up to the position of director of the car and truck department. He had previously studied business economics.
In 2004, with this track record and a good amount of know-how in association and stakeholder management, he founded Hooning Association Managers. The crowning feat of arms of his career so far is the foundation of the Superyacht Builders Association (SYBAss). Under his direction, the association has played a large role in making the superyacht industry visible in order to protect its best interests when it comes to regulatory issues and carve a niche to set the industry apart from the commercial maritime sector.
In 2017, together with major players from the industry, he launched The Superyacht Life Foundation, a non-profit organisation tasked with creating a more positive perception of superyachting to help the industry thrive.