The SIOP Secretariat supports the Board and the SIOP members in pursuing the Society’s mission.
Susanne Wollaert
Chief Executive Officer
Susanne leads the day-to-day operations of the Society, working closely with the Board and members to advance organisational objectives and ensure SIOP continues to respond effectively to an evolving global healthcare environment.
Tzvetomira (Tessie) Laub
Chief Programs Officer
Tessie is responsible for leading the implementation of SIOP’s Strategy 2026–2030 and overseeing the delivery and coordination of the Society’s programmes.
Olga Kozhaeva
Director of Policy Affairs
Olga leads SIOP’s advocacy activities, manages relationships with key policy stakeholders including the WHO, and supports the work of the Advocacy Committee.
Nancy Anderson
Marketing and Communications Manager
Nancy leads SIOP’s marketing and communications strategy, overseeing channels, content, and campaigns to strengthen engagement, visibility, and impact.
Anelia Atanasova
Administrative Coordinator
Anelia supports the Secretariat, Board of Directors, and leadership of SIOP’s Networks, Committees, Working Groups, and Task Forces, contributing to the Society’s day-to-day operations and administration.
Grigor Nalbantov
Membership Coordinator
Grigor supports SIOP’s membership activities and processes, drawing on his legal background to contribute to governance, compliance, and member engagement.
Julia Georgieva
Programme Coordinator
Julia supports the SIOP Continental Branches, their respective Boards, and the Country Ambassador program, contributing to the administrative management, programmatic initiatives, and digital communications of SIOP’s international activities.
The SIOP Secretariat is available to answer any questions and to give more information on the various activities of the Society.
The SIOP Secretariat does not respond to any questions regarding treatment and is not in the position to assist patients medically and/or financially. For such questions, we recommend that you consult our partnering family and patient organisations’ country offices and contact them directly.
SIOP Office, Stöcklen 16, 6344 Meierskappel, Switzerland
Tel: +41 78 687 9163
info@siop-online.org
