There has always been, since the very early days of aviation, some form of control exercised over air traffic, an attempt to curtail random activities. The earliest example is perhaps that of the somewhat unfortunate individual who was obliged to stand for long periods in a highly dangerous position at the end of a paraffin flare path. This example shows how soon it was realized that where a collection of individual units are all trying to get to the same place, some of them possibly at the same time, some co-ordination and orderliness must be introduced, and that this could only be achieved by some third party. It was soon seen that certain difficulties prohibited individual countries from making their own decisions on these matters and that, like the high seas, aviation requires a common ‘highway code’. With the ending of the first world war, and the beginnings of international aviation, came the formation of the International Commission for Air Navigation, which had amongst its objects the agreement between contracting states on standardization of rules of the air, and of visual and aural signals. It might well be said that, out of I.C.A.N., air traffic control was born in the period 1919–20.