To deepen the understanding and collaboration between the world's spiritual traditions is a core mission of Rabbi Soetendorp's life. For over 40 years he is untiringly active on the local, national and international level to strengthen the bonds of trust and friendship between the different faiths.

This way, he was co-chair of the Global Forum of Spiritual and Parliamentary Leaders for Human Survivial, which brought together leaders such as the Dalai Lama, Mother Theresa and Al Gore in the early 1990ies, he helped to create the "C100" - the Council of 100 Leaders in Islam-West Dialogue of the World Economic Forum and supported the three World Congresses of Imams and Rabbis for Peace, which took place between 2005 and 2008.

Among others, his current affiliations include: 

The Elijah Board of World Religious Leaders, facilitated by the Elijah Interfaith Institute in Jerusalem where Rabbi Soetendorp serves on the steering committee. The Board brings together some of the world's most prominent religious figures from Judaism, Islam, Christianity, Buddhism and the Religions of India. It provides a platform for sharing ideas and wisdom and addressing today's global problems.

The Safe the Jordan International Adovacy Campaign initiated by EcoPeace / Friends of the Earth Middle East to engage Jewish, Muslim and Christian communities in support of the ongoing advocacy efforts to rehabilitate the lower Jordan River. 

The European Council of Religious Leaders which is led by Religions for Peace, one of the largest international coalitions of representatives of the different faith traditions. 

The European Gathering of Jewish and Muslim Leaders, brought together by the Foundation for Ethnic Understanding and the World Jewish Congress, bringing together more than 50 leaders of Jewish and Muslim communities in Europe.

The "Prinsjesdagviering" - Each year, since 2000, the opening of the Dutch Parliament is preceded by a festive ceremony that includes the blessings and prayers of the key religious and humanistic traditions in the Netherlands. It has proven to be a very successful and inspiring event that provides a gravity and spiritual background to the beginning of the parliamentary sessions and serves as a vital sign of the magnificent cultural and religious diversity in Dutch society.

 Buidling on the expertise Rabbi Soetendorp has gained over the years, the Soetendorp Institute developed a "Faith and Leadership" Training Course for young adults where the participants are provided with skills necessary for responsible leadership and constructive dialogue both within their faith community and between communities of different faiths.