Klaas joined the IMO coregroup in January 2007.

From 1995 to 2007 he has been a part-time preacher in the Protestant church community in Wijk bij Duurstede, a small city in the Netherlands, living there since then with his spouse Jolande. He is father of two sons, Joram and Matthijs and one daughter, Carmen.

Klaas has studied theology at the theological university in Kampen and has written his thesis on the meaning of the philosophy of Fr. Nietzsche in the interpretation of the Dutch theologian K.H. Miskotte (1894-1976). As a preacher he accompanied the religious community to integrate the meaning of holy stories in the personal biography. As a consultant on horizontal leadership Klaas considers himself as taking care for the soul of people and organizations. The question how individual persons connect their inner life to the processes of work and the community has his warm and professional interest.

In 2021he published a book about the ‘Soul of Language’ (only in Dutch available).