Background: Analysis of (s-1, s) and Order-Up-To Policies -- Background Concepts: An Introduction to the (s-1, s) Policy under Poisson and Compound Poisson Demand -- An Exact Model for a Depot-Base Two Echelon Inventory and Repair System -- Tactical Planning Models for Managing Recoverable Items -- A Continuous Time, Multi-Echelon, Multi-Item System with Time-Based Service Level Constraints -- …