In its general sense, a contract of affreightment is any contract for the hire of a ship. However, it has a specialised meaning, that is, a contract for a series of voyages involving bulk cargoes.

BIMCO, the Baltic and International Maritime Council, publishes two forms to cover this type of contract: a Standard Volume Contract of Affreightment for the Transportation of Bulk Dry Cargoes, codenamed Volcoa, and a Tanker Contract of Affreightment, codenamed Intercoa 80, this latter being issued by INTERTANKO, the International Association of Independent Tanker Owners.