The overriding aim of material managers is to maintain a consistent flow of materials for production. This seemingly straightforward task has a range of potential difficulties to overcome including incorrect bills of materials, inaccurate stock-taking, shipping and receiving errors, unreported scrap, and production reporting issues. Planning, organising and controlling the flow of materials means it is possible to manage purchasing and shipping to coincide with a manufacturing process and the final delivery of products. While material managers oversee the inventory management needs of a company, the actual procurement of materials may be undertaken by a separate purchasing team. Material managers don’t just manage the flow of materials to ensure on-time delivery, but also seek to manage costs and quality through the supply chain. Keeping track of the availability of raw materials and products can also deliver cost savings and ensure a maximum return on working capital. Materials are usually classified as either direct or indirect materials. Direct materials are those that are required for a finished product, while indirect materials are those that do not directly generate the final product. In either case, inventory management is a vital aspect of material management.