Incoterms focus on the seller's delivery obligation. The precise distribution of functions and costs in connection with the seller's delivery of the goods would normally not cause problems where the parties have a continuing commercial relationship. They would then establish a practice between themselves («course of dealing») which they would follow in subsequent dealings in the same manner as they have done earlier. However, if a new commercial relationship is established or if a contract is made through the medium of brokers - as is common in the sale of commodities -, one would have to apply the stipulations of the contract of sale and. whenever Incoterms 2000 have been incorporated into that contract, apply the division of functions, costs and risks following therefrom.
It would, of course, have been desirable if Incoterms could specify in as detailed a manner as possible the duties of the parties in connection with the delivery of the goods. Compared with Incoterms 1990, further efforts have been made in this respect in some specified instances (see for example FCA A4). But it has not been possible to avoid reference to customs of the trade in FAS and FOB A4 («in the manner customary at the port»), the reason being that particularly in commodity trade the exact manner in which the goods are delivered for carriage in FAS and FOB contracts vary in the different sea ports.