Supply Chain Optimization applies OR techniques to design and operate supply chains efficiently. Key decisions: (1) Strategic - network design (facility locations, capacities); (2) Tactical - production planning, inventory positioning, transportation modes; (3) Operational - vehicle routing, warehouse operations, order fulfillment. Models integrate: facility location, inventory optimization, transportation, and demand forecasting. Objectives: minimize costs, maximize service levels, improve responsiveness, manage risks. Techniques: mixed-integer programming, stochastic optimization, simulation, and multi-objective optimization. Challenges: uncertainty (demand, supply, costs), scale (global networks), and coordination (multiple parties). Modern topics: resilient supply chains, sustainability integration, and digital supply chains with real-time optimization.