About Us

Established in 2000, Mandaat has become a leading Interim Management provider both nationally and internationally. The company aims to be practical and personal, focused on solutions and results. Mandaat joined WIL Group in 2016, to strengthen and grow its international footprint. Its objective is to provide managerial support so that clients are able to drive successful business implementations.

Underpinning that objective, Mandaat supports its clients by providing highly experienced management professionals, as well as coaching and advice for organizations in challenging times. It also provides Flexpats – where experienced Dutch Interim Managers are expatriated to overseas subsidiaries of Netherlands-owned companies.

Via its strong Dutch network, Mandaat selects high performing professionals with specific functional and industry related background. Mandaat’s executive partners Diederik van den Biggelaar and Janco Duvekot are experienced Interim Managers themselves.

This has created Mandaat’s unique personal approach, where the company seeks to establish what type of specialist the client needs.  Its expertise has led Mandaat to become the recommended firm among banks in Holland to assist with the recovery and restructuring of companies in distress.

<p>Diederik van den Biggelaar</p>

Diederik van den Biggelaar

Date founded:


No. of employees:


Diederik studied economics at the university of Amsterdam and studied senior management at INSEAD.

He developed his entrepreneurial mindset early on as a student, as co-founder of the student discotheque Dansen bij Jansen and several restaurants. This was followed by an international career as a Heineken manager for many years, beginning in the on-premise market and concluding as Export Director Europe and Japan.

After Heineken Diederik's career path continued as a Group Director at Samas, CEO at De Boer Structures, Director/Owner of Perfecta, Co-founder of iKi Bier and Partner at Custom Management.

Contact Details


Bergseweg 28 F,
3633 AK Vreeland,
The Netherlands

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Phone number

+31 (0)88 626 3228



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