Dr. Ton van Nimwegen
Chair and Elected Trustee
Ton was elected to the Board of Trustees in 2017. He returned to the Netherlands after spending twenty years abroad. He started his career at Unilever, moved on to ABN AMRO and now works for Rabobank. Ton has a Ph.D. degree in Economics.
He is married to Ângela, a medical doctor from Brazil, and they have two children at ISA: Nathalia and Sebastian.
Peter Jun
Vice-Chair and Elected Trustee
Peter was elected to the Board of Trustees in 2018. He earned an MA in International Relations, with high honors, from the University of Amsterdam and a BA in Government (Political Science), cum laude from Harvard College (University).
Peter has been active in professional real estate investing since 1999, having worked for The Praedium Group, Lehman Brothers and Lone Star in New York and London. In 2006, he co-founded a real estate private equity firm, Arminius Group, which actively invests in German real estate. Peter also served on the Board of Trustees at the International School of Zug and Luzern (Switzerland). He has three children attending ISA: Alexander, Megan and Aidan.
Peter was born in South Korea and is a dual US and Dutch national.
Maaike Siemons
Secretary and Appointed Trustee
Maaike was appointed to the Board of Trustees in 2020. Born and raised in the Netherlands, Maaike has lived in Vienna, Singapore and Düsseldorf. She is married to Frans and together they have three sons, Guus, Bonno and Casper.
Maaike earned her degree in Dutch Law from the University of Utrecht. She started her career in Finance with Fortis Bank Utrecht and ING Bank in Vienna. From 1998 she trained to be a personal coach and mediator and worked for Raymakers Van der Bruggen, as mediator, facilitator and personal coach. In 2006 the family moved to Dusseldorf, where the boys joined the International School of Düsseldorf. Since 2008, Maaike has been a board member for ISD for 9 years. She served as Chairperson for 3 years and Vice-Chair for 4 years. In 2017 the family moved to Amsterdam and Casper, the youngest son, joined ISA in grade 11. For two years the family was part of the ISA community. Maaike and Frans are very thankful to ISA for the successful transition that Casper made. He graduated in 2019 and is now a student at Warwick University. Since returning to the Netherlands, Maaike has founded her own coaching company.
Dr. Samaya Nissanke
Elected Trustee
Samaya was elected to the Board of Trustees in 2020. Born in London, Samaya is British but has a truly international family and educational background. Samaya was born to a Japanese mother and Sri-Lankan father, whilst her husband is French. She graduated from the University of Cambridge with a degree in natural sciences (physics) and went on to the University of Paris to study for her PhD in astrophysics. As an astrophysicist and university professor, Samaya has travelled extensively spending her postdoctoral fellowships in Toronto, Canada and Los Angeles/Pasadena, California as well as Boulder, Colorado. Samaya has worked in the Netherlands for a number of years and is now a professor at GRAPPA, where she holds a joint position in the Anton Pannekoek Institute (Astronomy) and Institute of High Energy Physics, University of Amsterdam. As a passionate advocate for women and girls to enter STEM and physics, she recently founded and Chairs the National NL astronomy equity, diversity and inclusion committee. Samaya’s son attends Lower School.
Giovanna Manto
Elected Trustee
Born and raised in Italy, Giovanna graduated cum laude in industrial engineering and worked in the UK, US, and Italy in a variety of corporate positions for the FCA group and EDF before becoming an executive coach and a facilitator for organizational transformation in 2011. Giovanna earned with distinction a degree in clinical psychology for organizations at INSEAD.
Together with her husband Michele, she lived and worked in France, Switzerland, and Germany before arriving in the Netherlands. They have two kids, Matilde and Vittoria, both attending Upper School at ISA. Since 2013, Giovanna has contributed to the School Community through the PTA and the PAC.
Mastering a number of proven concepts and research-based tools, Giovanna is passionate about supporting teams to develop resilient and compassionate leadership.
Kathrin Haeusler
Elected Trustee
Kathrin was elected to the Board of Trustees in 2022. Born in Germany, Kathrin has a Master’s degree in Business Administration and Marketing from the University of Passau (graduating with distinction). After graduation, she worked as an assistant at the Marketing faculty of Prof. Dr. Helmut Schmalen where she also taught Marketing classes. She has worked for over a decade in various roles in the fields of Strategic Marketing with a focus on customer relationship programs, market research and database management all over Europe.
Nearly 20 years ago, Kathrin and her husband Christoph decided to live an international life which took them to seven countries on three continents. They have three children (19, 17 and 14 years old) who have been to seven different (mostly IB) schools. Her oldest son graduated this year at ISA, her daughter is now in grade 12 and her youngest son is in grade 9.
Esmond Douma
Appointed Trustee
Esmond was appointed to the Board of Trustees in 2022. He has always lived in the Amsterdam and Amstelveen area. Esmond earned his degree in Dutch Law from the Vrije Universiteit (Free University) in Amsterdam. For more than 25 years, Esmond has been a barrister and is specialised in employment law. Esmond has a sound track record regarding board memberships: e.g. Amstelveen Entrepreneurs Association, Golf club Olympus, parents teacher association primary school De Horizon in Amstelveen, Platform C in Amstelveen (music school, people’s university, art). Esmond is married to Jenny (born in Malta), and together, they have twin sons. Esmond loves (playing) soccer and golf.
Jon Webb
Appointed Trustee
Jon was appointed to the Board of Trustees in 2020. Jon retired recently from full-time work after a career in international publishing and information management. Most recently Managing Director of IATA (Netherlands) B.V, the publishing arm of the International Air Transport Association, he previously held roles managing businesses in the legal, scientific, medical and consumer information industries in the UK and USA.
Jon has an undergraduate degree in International Relations, earned an MBA (with Distinction) from the City University Business School in London and an Advanced Management Diploma from the Wharton School, University of Pennsylvania. Since 2007 Jon and his family have lived in Amstelveen. His three children attended ISA and between 2018 and 2020 Jon was Co-Chair and Treasurer of SHARE, helping raise funds to support ISA students’ CAS and Service as Action activities.
Equity and Inclusion in STEM
“In my career I’ve noticed that having different backgrounds and different origins brings different viewpoints and creativity to the table, and that’s when you see real progress.”
– Dr. Samaya Nissanke
