In the context of the EU CBRN Centers of Excellence (EU CBRN CoE) initiative, under the Patronage of the Prime Minister of Lebanon, ARZ 2023 was developed: a 4-day inter-agency CBRN field exercise that focused on key aspects of detection and first response against CBRN security threats. The main objective of ARZ 2023 is to test the capacities to counter CBRN risks, test emergency response procedures, and identify best practices.