de Jong


I have been enthusiastically fulfilling my role in Yellowstone International’s finance department since April 2008. Our team has now grown to four driven professionals, including Lisette, Maja and Jolanda. Together, we bear responsibility for all financial matters of our subsidiaries, Yellowstone Managed Services and Yellowstone Contract Management. Our duties cover a wide range of financial activities, including accurately processing timesheets, managing accounts receivable and payable, taking care of salary and creditor payments, and much more.
I am also responsible for the administration of our self-employed staff.

I’m not available on Fridays.

van der Steen


Yellowstone International has grown rapidly, which is why I joined the finance team at the beginning of 2019. Together with three colleagues, we ensure correct handling of financial tasks, including invoicing, registration and timesheet processing.

I also check pension declarations, take care of audits, sick leave and complaints.

I’m not available on Wednesdays and Fridays after 12 pm.



From September 2021, I joined Yellowstone Contract Management to support the finance department. Here, I support my colleagues Marian, Lisette and Jolanda in handling various financial tasks including time processing and invoicing.
I am also responsible for the registration and handling of margin contracts with various parties.

I’m not available on Mondays.

van Genugten


I have been working in the Finance department of Yellowstone International since Oct 2022. Together with my 3 other colleagues Marian, Lisette and Maja, we take care of the correct handling of financial tasks such as processing time-sheets and invoicing.
I also contribute to the administration of sick leave. Every day is a new challenge in a friendly environment.

I’m not available on Thursdays.