This document discusses material control and how to effectively manage inventory levels. It describes two key aspects of material control: physical control and controlling investment in materials. Physical control involves limiting access, segregating duties in purchasing, receiving, storage, and recording. It also stresses the importance of accurately recording inventory transactions. Controlling investment focuses on setting order points and economic order quantities to minimize total inventory costs by balancing ordering and carrying costs. The economic order quantity model aims to determine the optimal order size.