So, you’ve noticed my posts, and you wanted to check out who I am and what I do? As my website (accessible via the menu on top) is in Dutch, I’ll give you a brief overview in English below.

Hi, my name is Denny Portier-Terpstra and I’m an IRCM-registered and internationally working executive coach, mentor & consultant.
With a background in HR & leadership – and having gained experience as a founder and business leader of a successful start-up myself – over the past 2 decades I’ve been coaching, mentoring and guiding business leaders.
Executive coaching, mentoring and consultancy are different ways of working with business leaders to help them define and achieve development goals for themselves, their team(s) and/or their business(es).
What sets me apart from my competition, is that I combine these three professions in my approach, which fast-tracks development.
Do you have a leadership challenge that you would like to tackle ASAP?
I’m yet to meet the first business leader who doesn’t have a challenge (or two) and doesn’t want it resolved. But not everyone is looking for help with doing so. And let’s be honest, most things aren’t that hard to figure out by yourself, it just takes some time.
But what if time is of the essence? More often than not, we discover our development needs right in the middle of critical times, when we know that we need to step-up our game fast, and don’t have a lot of time to figure out how. At times like that, my support will be of the most value to you!
Leadership and learning are indispensable to each other.
John F. Kennedy
What I can help you with:
Given my background in HR & leadership, I can help you with a broad range of challenges, which include:
– Personal challenges, like setting boundaries, increasing self-confidence, stopping procrastination, taking decisions, setting priorities, time-management, establishing a healthy work/life balance, developing executive presence, …
– Team challenges, like improving team spirit, increasing effectiveness, solving communication or collaboration problems, …
– Organizational challenges, like employee challenges, cultural challenges, structural challenges, change challenges, …
And many more!
What I can’t help you with:
As a chief exec, exec, and non-exec board member of various business across industries, I’ve gained experience and developed a good understanding of most aspects of general business management. However, I’m not an expert in legal, finance, R&D, or tech.
The process:
Don’t expect an online program, group program, or the traditional approach of a lengthy meeting every so many weeks. Although these approaches can be effective, they aren’t quick nor bespoke, and therefore aren’t the go-to-solution for urgent challenges.

Although the various stages of the process are roughly the same (see picture above), I will work with you personally to tailor my support around your specific challenge, timeline, agenda and preferences. With most of my clients, the majority of the work is done virtually by – often ad-hoc – phone or video calls and messages, but I do prefer to meet face-to-face at least once to meet each other in person and go through the Discovery and Plan.
As no situation is the same, it’s hard to give a general timeline to reach Result(s), but on average it takes my customers 1-3 months.

Want to know more?
Feel free to look at the rest of my website, check-out my LinkedIn profile, Google me, or call/email/WhatsApp me for more info. You can find the relevant info and links at the top and on the bottom of this page. Or simply leave me a message with your contact details and availability below, and I’ll get back to you as soon as I can.
Please note:
– I’m just a team of one, and I can only work with a few customers at any given time to provide high-quality support
– My high-quality support is priced accordingly
– I’m located in the CET timezone and work between 8AM-22PM CET
I appreciate your interest, but kindly ask that you do not use this form or my other contact information for unsolicited messages or sales pitches
Tel: +31650207974
Email: info@onaworkmission.com
Lucellestraat 138-III
1055JA Amsterdam
KvKnr: 70692661
BTW IDnr: NL001932897B77