Interpol and the United Nations Environment Programme (UNEP) released the results of the month-long operation “30 Days at Sea” launched between 1 and 31 October, where 122 national coordinators supported the international law enforcement operation against maritime pollution. As a result of this global effort, 276 law enforcement and environmental agencies detected over 500 offences across 58 countries. The narrative behind the operation puts an emphasis on the risks presented by marine pollution and the needs to address them at the international level. Moreover, “30 Days at Sea” aimed at raising awareness on the impact of marine pollution on economic development and human and environmental security. Innovative technologies such as satellite imagery, aerial surveillance, use of drones and night vision cameras helped the authorities to detect the offences. Overall, the operation exposed serious cases of marine contamination in different contexts, involving different actors: during the operation, two ships collided in French waters, risking heavy water poisoning. The incident was handled, and the contamination was contained thanks to the manoeuvres used during the exercise.