Tjitske started her career in 1997 as a trainee at PostNL, where she had several managerial positions at the Marketing and Client Services department. In 2006 Tjitske moved to ING NL. In a period of 5 years she was promoted to Head Sponsoring, Events & Activation. She is responsible for the sponsorship of the Dutch National Football team, amateur football, the Rijksmuseum and Royal Concertgebouw Orchestra. Under her management ING (NL) has won several national and international communication and sponsor awards. Tjitske was named the most influential person in the Dutch sponsoring industry in 2019 and 2020..