06 - 21943204

Who am I

About Sjaak Kolvenbach



The power of openness

Openness, honesty and vulnerability; these are the three pillars upon which I build my work.
My years of experience have taught me that these pillars are key to becoming more self-aware and more conscious. They are the core of who I am. When I am really being me, I embody the strength and leadership that creates trust and connection.

Building on what’s already there

In my client engagements I seek to fully understand and work with the existing energy and dynamics. I look at people’s strengths and the power within a group. I honor that the positive energies of the people or the group remain. I do not use tricks or fads. They don’t stick. It’s only when people start to recognize their own patterns and defenses that magic happens, that real sustainable change takes place. This approach keeps everything very practical and within reach.

“Great leaders are vulnerable.

It gives them the power to be direct and honest.”

From flour to flourishing

​I grew up in my father’s bakery. A genuine family business, that we ran together for many years. But at a certain moment I decided to go my own way. I took various management positions inside the food industry. That turned my focus onto what it’s all about: what does it mean to be an effective leader in my vision? And that is: effective and personal leadership. The next step for me was becoming a leadership trainer. I pursued many national and international courses and certificates, leading to becoming the senior trainer I am today, working with clients at every level of the organization from individual contributors up to executive level leaders. My work gives me a lot of positive energy.

A selection of mine

education and certificates

  • ITIP, School for live and work
  • The Human Element®
  • The FIRO-B ®
  • Radical Collaboration®
  • Implicit Career Search®
  • The Wilfred Jarvis Institute, Four Quadrant Leadership.
  • Myers-Briggs Type Indicator® (MBTI®)
  • MTRi® Myers-Briggs Team Role indicator
  • The Natural Step level 1 ‘Sustainability for Leaders’.
  • Management issues, Model-learning in practice

“Sjaak changed my view on ‘group trainings’ dramatically. He really lets you see how people feel in different situations. With this in mind, I can now better understand how people react. I asked Sjaak to surprise me with this training, and he did!”

Olaf Schulte

Groupleader Sales, Vanderlande Industries GmbH



Emmastraat 39, 6862 GS Oosterbeek

Phone number

+31 621943204