Team Members

Meet the Team

Ilse Lettinga

Manager Nudge Global Impact Challenge

Jan van Betten

Founder Nudge

Maëlle Tschumi

Project and Communications Manager

Daniella Vento

Project management and communications intern

Vittorio Ceschi

Social media & communications intern

Precious Mando

Manager of the Nudge Alumni Association

Rick Koster

Founder LeaderScope

Yori Kamphuis

Leadership and communications advisor, LeaderScope

Ama van Dantzig

Moderator of the Grand Finale Closure Event

Bibi Veth


Rianne Hammenga

Event Manager Nudge Global Impact Challenge

Short Biographies

Ama van Dantzig, Moderator of the Grand Finale Closure Event

Ama is a creative thinker, speaker, facilitator, moderator, and an experienced Co-Founder with demonstrated history of working in the non-profit organisation management industry. Her skills revolve around non-profit organisations, sustainable development, international relations, project coordination and non-governmental organisations. Ama divides her time between Accra and Amsterdam – building bridges between seemingly opposite worlds. With vast experience on the ground in many countries and communities, Ama believes in the ability of people to generate ingenious solutions for the challenges of our time. 

She is one of the Co-Founder at Dr. Monk, an international innovation studio and project incubator, with a global network of talented people committed to making the world a clean, just and simply beautiful place, through developing concepts, strategic advice and innovative research. Their headquarters are in Amsterdam and Accra.


Ilse Lettinga, manager Nudge Global Impact Challenge

Ilse has worked as communication manager at ABN AMRO’s Corporate Communications after 10 years at several positions in the advertising industry. She joined Nudge 7 years ago and has been involved in the creation, strategy and development of the Nudge Global Impact Challenge from the start.
She is responsible for the overall project management and communications of the Nudge Global Impact Challenge.
“I am always overwhelmed by the energy, passion and power of the young professionals attending the Nudge Global Impact Challenge. I feel privileged to support the participants in their development as leaders in sustainability.”


Jan van Betten, founder of Nudge

Jan van Betten started his career as a junior company lawyer with Philips before joining British American Tobacco. In 2005 he moved with his family to Munich to take up the role of CEO of Reed Elsevier Deutschland GmbH. Inspired by the development of a consumer platform for sustainable consumption in Germany, he started the social enterprise Nudge and Nudge Academy in the Netherlands in November 2010. Working with young talents from all over the world on their leadership for a sustainable future has become his passion and main focus.

Jan is the Co-Founder of the One Africa Leadership Development Program, see their website for more information:

He is also currently active as a non executive board member for several profit- and not-for-profit organizations.

Rianne Hammenga, Event Manager Nudge

Driven by a wish to work for brands that add more to the world, she joined Nudge four years ago. Starting from sales and relationship management with the Friends of Nudge and partner organisations, she moved into the field of communications. In this position she enjoys the challenge to encourage people to positive behavioural change.

This year she is, for the second time, involved in the Nudge Global Impact Challenge as event manager of the Nudge Summit. With her endless energy and hands-on mentality, this role is wonderfully suited to her! Looks forward to see our joint efforts brought together in the Nudge Global Impact Challenge.

Rick Koster, Founder & CEO LeaderScope

During his work as biology teacher at multicultural high school in Amsterdam, Rick joined The Leadership Group to support leaders in their personal development and communication. In leadership programs in Europe, Northern Africa and the Middle East, Rick shares his passion for interpersonal learning, presentation and non-verbal communication. In supporting others to get the best of themselves, his credo is: feel positive, think creative.

Yori Kamphuis, Leadership and communication advisor, The Leadership Group

“In what I do, I look for passion in others. Making things happen. Striving for goals with passion.

It is my goal is to help provide solutions for the challenges our world faces. And to spread positive energy. Through sharing thoughts, running a business, collaborating and creating mutual understanding in our changing world.”

Specialties: Cyber Security, Team building, People management, Leadership, Motivational Speaking