The issue opens with Matteo Tondini’s reflections on the legality of State-run espionage under international law in the light of the current ‘neo-realist shift in international relations’ which exacerbates the existing competition between States and, thus, becomes a propitious space for espionage activities. The interaction and potential interference of those activities with States’ international legal obligations open up the debate on the legality of espionage, its scope and its limits.

Shifting to the field of human rights and humanitarian law, the subsequent piece by Hanna Bourgeois and Jean-Emmanuel Perrin examines the question of the use of force for mission accomplishment in the context of contemporary operations. Mapping the existing legal framework applicable to the use of (potentially lethal) force, both in and outside the conduct of hostilities, the authors raise questions pertaining to its suitability to effectively govern international military operations abroad.

Recent years have been particularly rich in legal debates surrounding the terrorist threat and the means to fight terrorism domestically and abroad. Legislative and jurisprudential developments have caught the commentators’ attention in several countries, including Belgium. Article 141bis of the Belgian Criminal Code contains the so-called ‘IHL exception’ that excludes the application of provisions on terrorist offences to ‘actions by armed forces during periods of armed conflict, which are governed by international humanitarian law’. Two contributions – by Marine Wéry and Julien Tropini, respectively – comment on different aspects relating to the application and interpretation of this particular provision by the Belgian courts. While Wéry examines the jurisprudential scope and use of the concepts of ‘armed conflict’ and ‘armed forces’, Tropini analyses the notion of ‘foreign terrorist fighters’.

Finally, this issue contains the report from the Second International Conference ‘Silent leges inter arma?’ organised by the Belgian Group of the International Society for Military Law and the Law of War and held in Bruges (Belgium) in September 2018. A great platform allowing for stimulating debates between practitioners and academics, the International Conference tackled several interesting questions ranging from the law applicable to peace operations to the use of various types of weapons in specific contexts. Summaries of the presentations and discussions are included in the report.