The present report provides an overview of the international and EU regulatory context of countering the deliberate misuse of CBRN materials and knowledge. The report argues that upholding the international norms against WMD non-proliferation enshrined in the existing international and EU regulations and arrangements in the area of WMD arms control and disarmament, relevant export and import control, and counter-terrorism is an essential requirement for preventing the hostile misuse of CBRN materials and knowledge.