Inventory optimization is the most complex problem in supply chain management; most firms struggle with dramatic swings between overstock and understock. For these companies, setting inventory targets is often a guessing game based on individual judgment and powered by manual processes. Multi-echelon inventory optimization (MEIO) can solve complex inventory problems. This report gives application development and delivery (AD&D) professionals insights into inventory management challenges, describes the benefits of MEIO, and outlines best practices for deploying it.