1. The importer may come in with an initial inquiry requesting a price quotation for a certain type of quantity of merchandise.2. The seller, in turn, responds with the desired information. Usually, this response can already by interpreted as an offer that is binding on the exporter, provided the importer accepts it within a reasonable period of time.3. After many rounds of negotiation, when an effective offer is effectively accepted by the buyer, the transaction is completed and a contractual relationship between the buyer and seller is concluded.4. According to the international trade practice, the seller and the buyer still have to sign a written sales contract or confirmation, binding on them all, to further define their rights and obligations respectively