To ensure the Tallinn Manual is relevant and reflecting different views, the CCDCOE invites experts around the world to contribute to the revision of this globally influential resource for legal and policy advisors dealing with cyber issues:

Contribute to the Tallinn Manual 3.0 here 

The Tallinn Manual has long been the flagship research initiative of the CCDCOE. The original Tallinn Manual (published in 2013 by Cambridge University Press) addressed the most severe cyber operations – those that violate the prohibition of the use of force, entitle states to exercise their right of self-defence, or occur during armed conflict. The Tallinn Manual 2.0, published in 2017, built on that work by considering the rules of international law governing cyber incidents that states encounter on a day-to-day basis but which fall below the thresholds of the use of force or armed conflict. The Tallinn Manual is available in both paper and electronic copies from Cambridge University Press.

The Tallinn Manual has become an influential resource for legal advisers and policy experts dealing with cyber issues. Emerging State practice and the taking of public positions on international cyber law many States since the Manual’s publication necessitates an update of the 2017 edition. Accordingly, in 2021, the CCDCOE has launched the Tallinn Manual 3.0 Project, a five-year venture that will involve the revision of existing chapters and the exploration of new topics of importance to States. In addition to State practice and States’ official statements on international law, the activities and statements of international fora, such as those at the UN and regional levels, academic scholarship, and multi-stakeholder initiatives involving governments, industry, and civil society will be considered.

The CCDCOE will provide project management and research support and offer technical and policy consultancy.

The process will engage a broad community of international law specialists as researchers and peer reviewers. As with the Tallinn Manual 2.0, an International Group of Experts consisting of renowned international law scholars will be invited to develop and approve the Manual. An essential facet of the project is engagement with States, which will be afforded the opportunity to offer national perspectives for consideration in the revision of the Manual.

Professor Michael Schmitt (University of Reading, CCDCOE Senior Fellow), who directed both the 2009-2013 and 2013-2017 Tallinn Manual efforts and was their General Editor, will serve as the Director of the Tallinn Manual 3.0 project. He will be joined as Co-General Editors by Ms. Liis Vihul (Managing Editor of Tallinn Manual 2.0, CEO of Cyber Law International, and an alumnus of the CCDCOE) and Professor Marko Milanović (Professor of Public International Law at the University of Nottingham and co-editor of the EJIL:Talk! blog of the European Journal of International Law).

The nature of the Tallinn Manual will remain unchanged; it will continue to be a non-legally-binding scholarly work by distinguished international law academics and practitioners intended to provide an objective restatement of international law as applied in the cyber context. It is policy- and politics-neutral and will not represent the legal position or doctrine of any State or international organisation, including the CCDCOE. As with the previous editions of the Tallinn Manual, the project’s leadership is committed to objectivity, in particular by including all reasonable views regarding the interpretation and application of international law in the cyber context.