The Provisional Technical Secretariat

The main function of the Provisional Technical Secretariat (PTS) is to assist the Preparatory Commission in establishing a global verification regime to monitor compliance with the comprehensive ban on explosive nuclear testing. This regime – sometimes referred to as a "global alarm system" – is 90% operational and transmitting data 24/7 to the CTBTO’s International Data Centre (IDC) in Vienna.

The PTS also promotes the signing and ratification of the CTBT so that it enters into force as soon as possible. As well as engaging directly with states, it assists Member States in special outreach activities such as Article XIV Conferences and Ministerial Meetings. It provides workshops and training to promote the Treaty and strengthen the verification regime and conducts outreach to other stakeholders including scientific and research communities, youth, civil society, the media and general public.

The PTS began work in Vienna on 17 March 1997 under the auspices of Executive Secretary Wolfgang Hoffmann. He was succeeded by Tibor Tóth on 1 August 2005. On 1 August 2013, Lassina Zerbo became the organization’s third Executive Secretary. Robert Floyd took office on 1 August 2021 as the fourth Executive Secretary of CTBTO. The Executive Secretary is the only PTS official appointed by the Preparatory Commission and reports directly to the Commission on PTS operations.
The Secretariat is composed of five divisions: the International Monitoring System Division, the International Data Centre Division, the On-Site Inspection Division, the Legal and External Relations Division, and the Division of Administration. 
Nationals of all States Signatories are eligible to serve in the PTS, which has nearly 300 staff from around 90 countries.

The Organizational Structure of the PTS

The Organizational Structure of the PTS - Sept. 2022

Internal Audit and Oversight

The Internal Audit and Oversight Section is an independent and objective internal oversight mechanism which contributes to the effectiveness of governance, risk management, and control processes of the Provisional Technical Secretariat (PTS) of the CTBTO.

By carrying out assurance, advisory and investigation services, the Section helps improve PTS processes and procedures through a systematic, disciplined approach aimed at assessing, strengthening, improving and adding value to the organization's operations and overall risk and control environment.

Being operationally independent in the conduct of its duties, the Internal Audit and Oversight Section is part of the Office of the Executive Secretary and the Chief of the Section reports directly to the Executive Secretary. The results of its work are shared annually with States Signatories and presented to the Advisory Group and Working Group A in order to enhance transparency and accountability.

Learn more about the Internal Audit and Oversight Section


CTBTO Executive Secretary: 
Robert Floyd, Executive Secretary 

Administration Division: 
Uday Dayal, Director 

International Data Centre Division: 
Dounia Keda, Director 

International Monitoring System Division: 
Xyoli Pérez Campos, Director

Knowledge Management and Human Resources Services: 
Deepti Choubey, Director 

Legal and External Relations Division: 
Junan Zhang, Director 

On-Site Inspection Division: 
Oleg Rozhkov, Director