In fact, the bill of lading does not replace the contract of affreightment but it is legally accepted as the confirmation and the realization of the contract of affreightment.
Nearly no legislation gives a clear definition of the bill of lading. Some local legislation such as Article 59 of Book II of the Commercial Code (Belgian-) writes that it is a receipt for the goods which the Master takes in charge. Article 1 of the new “Rules of Hamburg” which were accepted at the Diplomatic Conference of Hamburg in March 1978 gives of the bill of lading the following definition:
"Bill of Lading means a document which evidences a contract of carriage by sea and the taking over or loading of the goods by the carrier, and by which the carrier undertakes to deliver the goods against surrender of the document. A provision in the document that the goods are to be delivered to the order of a named person, or to order, or to bearer, constitutes such an undertaking."
(See also the Hague Rules and the Hague-Visby Rules and its Protocol.)