In order for a company to be competitive in modern market conditions, it must establish its own production strategy that answers the fundamental questions of what, how, and for whom it produces. It must align its business policy with the established production strategy, and inventory management policy is one of the most important since the price of incoming raw materials accounts for most of the cost of production. Since high inventory levels incur costs in terms of inventory holding costs and working capital commitment, and low inventory levels can lead to production interruptions, the company must determine the optimal inventory levels using modern information systems and mathematical economic models. Specifically, the Just-In-Time method is explained as the most efficient method of inventory management in a theoretical sense, as well as using the example of a small project-oriented manufacturing company that applies the Just-In-Time model to the production of products in small batches.