This briefing is based on thirty years experience in the installation, servicing and operation of supply chain software. It was written for the executive, manager or engineer considering installation of a warehouse management system. It may also have special value to those who are considering a replacement of their present system. We begin with the purpose of warehouse management systems and a description of their costs and benefits. The build-versus-buy choice is discussed. Organizational impact and the short and long-term effect on customers are described. The book then moves into a discussion of how to buy a WMS, the project team that must be assembled, the marketplace for commercial systems, the types of systems available and how to go about choosing among them, the creation of a Request for Proposal and the evaluation of responses. It ends with a methodology for justifying/funding a system and concludes with discussions of installation and ongoing operation and maintenance.