Inventory management is a method by which a business manages tangible resources and materials to ensure the availability of resources for use. It is a set of interdisciplinary processes comprising a full circle from demand forecasting, supply chain management, inventory control and reverse logistics. Inventory management is the optimization of stocks of manufactured goods, work in progress and raw materials. According to Doucette (2001), inventory management can sometimes be difficult. However, the need for effective inventory management is widely seen as a necessity rather than just a trend, as customer satisfaction and service have become a major reason for a business to stand out from its competitors. For example, Wal-Mart's inventory management is one of the largest contributors to the company's success; from the manufacturer's warehouse to the shelves, the company must orchestrate a symphony of the right products in the right places at the right time. Walmart serves its customers and members more than 200 million times per week in-store, online and on mobile devices. The company is able to offer a wide range of products at the lowest costs in the shortest possible time (Chandran, 2001). The main reason for Walmart's incredible growth is that its distribution centers are highly automated. There is no denying that inventory management is an important key to success at Walmart. This article will discuss the two main inventory management methods used by Wal-Mart: Requirements planning and just-in-time. We then write about technical ways to track inventories, such as RFID tags. We conclude by discussing how Wal-Mart, one of the world's largest retailers, manages its inventory. Material requirements planning