Not all institutions of international law of war at sea have stood the test of time. Several of them are no longer current at all; others have been subject to degenerative changes; and there are yet others that, while formally still in existence, even in established law, are vanishing through desuetude. "Days of favour" belong largely to this category. This institution applies to the situation of a ship at the commencement of armed conflict. In general terms, we can define it as a period of grace allotted by a party in an armed conflict to ships of its adversary. It allows these to leave an enemy port after unloading or loading goods, with the aim of enabling these vessels to sail to one of their own ports or to a neutral port, actions that the unexpected outbreak of war had hindered.