Business-to-business (B2B) refers to a situation where one business makes a commercial transaction with another. This typically occurs when:

• A business is sourcing materials for their production process, e.g. a food manufacturer purchasing salt.
• A business needs the services of another for operational reasons, e.g. a food manufacturer employing an accountancy firm to audit their finances.
• A business re-sells goods and services produced by others, e.g. a retailer buying the end product from the food manufacturer

Contrasting terms are business-to-consumer (B2C) and business-to-government (B2G).