This document discusses e-procurement models including pre-Internet EDI networks, B2E purchasing and requisitioning apps, and corporate procurement portals. It then summarizes different generations of trading exchanges like content communities, RFP/RFQ facilitators, virtual distributors and auction hubs. Later generations of trading exchanges focus on collaboration and providing additional services. Industry consortiums are forming as buyer or supplier consortiums to drive down prices through combined purchasing power. Reengineering procurement processes is key to deploying e-procurement solutions and reducing channel fragmentation.