Abstract: An online trading system and method for establishing hierarchies of online trading units having plural levels of authority and available trading resources is disclosed. Each of the trading units represents part of a structured organization that trades goods and/or services, such as a global corporation, institution or government entity. The disclosed system and method allow large enterprises to conveniently integrate their purchasing and selling departments into an online trading environment, while maintaining a centrally-defined, hierarchical control scheme to appropriately limit and monitor the trading activities of the various departments.