The second Air Navigation Conference sponsored by the International Civil Aviation Organization (ICAO) opened in Montreal on August 30, 1955. Technicians representing 26 countries members of ICAO, three non-member countries and five international organizations attended the Conference, which had on its agenda radio aids to final approach and landing, long-distance navigational aids, aircraft separation in high density traffic areas, visual flight rules, and minimum height rules. The Conference requested ICAO members to set up a system of reporting “near-misses” between aircraft in flight, with the purpose not of enforcing existing rules of the air by taking disciplinary action against the pilots concerned but, by a systematic analysis of near-misses and the determination of their causes, to find a way of avoiding them. The Conference noted that research was being carried on in regard to anti-collision lights, and recommended that member states forward to ICAO information on the results of their trials and experiments. The Conference also recommended that ICAO revise its international standards to prohibit all flights in controlled airspace between sunset and sunrise unless such flights were carried out under air traffic control from the ground, with specific permission from the appropriate authorities. After considering complications resulting from aircraft flying under Visual Flight Rules (not under ground control) in controlled airspace, the Conference proposed an amendment to the international standards on rules of the air which would bring under traffic control a number of such flights, and made several other recommendations designed to minimize the traffic complications resulting from flights not under ground control.