Electronic commerce (e-commerce) is a term commonly used to describe any form of online sales. Business-to-business (B2B) e-commerce refers specifically to sales that take place between businesses. A restaurant purchasing food supplies from a vendor via an online sales portal, a library purchasing books from a publisher’s online website, or a corporation purchasing access to training videos from an e-learning company are all examples of B2B e-commerce. This entry provides an overview of B2B e-commerce and explores its future. The entry covers trends in B2B e-commerce, its current state, and the history of the platforms and technologies that support B2B sales. The role of technology in fueling future growth is also outlined.