Multinational Design Evaluation Programme (MDEP)

MDEP was established in 2006 as a multinational initiative taken by national safety authorities to develop innovative approaches to leverage the resources and knowledge of the national regulatory authorities involved in the review of new reactor nuclear power designs.

MDEP incorporates a broad range of activities including:

  • Enhancing multilateral co-operation within existing regulatory frameworks, with a view to harmonisation of regulatory requirements and practices;
  • Facilitating multinational convergence of international and inter-governmental safety standards and safety goals through interactions with other multinational organizations, and industry;
  • Implementing the MDEP products to facilitate licensing of new reactors as well as oversight of their construction and commissioning activities.

A key concept throughout the work of the MDEP is that national regulators retain sovereign authority for all licensing and regulatory decisions.

Members and participants

MDEP members are national regulatory authorities of interested countries that already have commitments for new build or firm plans to have commitments in the near future for new reactor designs. Currently, the nuclear regulatory authorities of 6 countries participate in MDEP, which includes 2 design-specific working groups. The Nuclear Energy Agency facilitates MDEP activities by providing technical secretariat services for the programme, while the MDEP Management Board (MB) oversees the programme.

Further details about the organisational structure of MDEP can be found in the terms of reference.

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Current MDEP members include national regulators from:

The International Atomic Energy Agency (IAEA) also participates in key aspects of MDEP's activities.


MDEP's main objectives can be defined as follows:

  • to enable increased co-operation within existing regulatory frameworks;
  • to establish mutually agreed positions, influencing enhancements in the safety of new reactor designs.

It has been enhancing co-operation among regulators and improving the effectiveness and efficiency of the regulatory design reviews, which are part of each country's licensing process.

The programme has focused on co-operation of regulatory practices that aim at harmonising regulatory requirements.

MDEP products

One of the aims of MDEP is to work towards greater harmonisation of regulatory requirements. Co-operation amongst national regulators under MDEP has led to harmonization of regulatory positions and practices through the establishment of Common Positions, achieved through the activities of different design and issue-specific working groups.

MDEP produces Technical Reports that enable member countries to better appreciate similarities and understand the differences in national requirements and practices. The topics for technical reports were selected based on the issues arising from regulatory activities in member countries, safety implications, or the general need to have a better understanding of the topic. This has facilitated sharing experiences and is considered to be the basis of work on harmonisation.

For more information on MDEP's accomplishments to date and future work, consult the MDEP Policy Group Close-out Report and the Annual Reports.

Engagement with stakeholders

Successful interactions with stakeholders through MDEP have built links with regulators, industry, standards development organizations (SDO) and other international organisations, and have been beneficial in the review of different reactor designs. For instance, MDEP has brought together regulators, SDOs and industry, through the World Nuclear Association Co-operation in Reactor Design Evaluation & Licensing (WNA CORDEL), to discuss issues and clarify regulatory positions that have significant impacts.

MDEP is recognised as a unique multinational framework where new reactor vendors can participate on a regular basis. Furthermore, MDEP used the opportunities provided by workshops and conferences. MDEP held four conferences in 2009, 2011, 2014 and 2017, these events attracted approximately 600 participants. The conferences addressed topics on important common issues, such as new reactor activities related to the Fukushima Daiichi accident and more specific technical discussions.


As of 13 January 2022, Mr Alexey Ferapontov, Deputy Chairman of Rostechnadzor was elected as the Chair of the MDEP Management Board and Mr Abel Julio Gonzales, Senior Adviser to the ARN Board of Directors, was elected as Vice-Chair on 27 June 2022.

Working groups

In accordance with the terms of reference, the MDEP carries out its work through design-specific working groups. Working groups for each new reactor design will share information and co-operate on specific reactor design evaluations, construction, commissioning, and early phase operation. Participants in these working groups should be MDEP member regulatory authorities (and their technical support organisations) who are interested in a specific reactor design and are willing and capable of contributing positively to the group's activities. Design-specific working groups (DSWG) will be formed when three or more countries express an interest in working together. The current DSWGs are:

  • VVER Working Group was established to share information on the VVER safety review. Current members are regulators from China, Hungary, India, Russia and Türkiye.
  • HPR1000 Working Group was established in September 2017. Current members are regulators from Argentina, China, South Africa and the United Kingdom.

Under each of the design-specific working groups, technical expert subgroups (TESG) were formed to address specific technical issues.

Last reviewed: 16 May 2024