Book excerpt: While there are many books written on the basics of the "supply" side of the supply chain (i.e. strategic sourcing, sourcing/procurement, and purchasing), there hasn’t been much written on those areas from a Lean perspective. Considering that supply chain costs, primarily procurement and transportation, can range from 50 to 70% of sales, it's surprising that this area has not been fully explored. As a result, some companies tend to place too much emphasis on the traditional focus of reducing material costs instead of process improvement. Lean Demand-Driven Procurement: How to Apply Lean Thinking to Your Supply Management Process details the basic supply management concepts and processes (i.e. sourcing, procurement, and purchasing) in an easy-to-understand format in combination with various process improvement tools, methodologies, best practices, examples, and cases written from a Lean perspective. It focuses and pinpoints ways to identify waste on the supply side through improved processes and, in some cases, technology. Applying Lean principles to procurement and purchasing processes identies non-traditional sources of waste, and in some cases, creates a paradigm shift that results in additional benets to the entire supply chain.