I. Introduction.- Why Service Differentiation? Why Now?.- II. Theoretical Foundations for Service Design.- Priority Service Methods.- Real Time Pricing: Bringing Added Value to Utility Programs.- III. Understanding the Customer’s Needs.- Modeling Customer Preferences; Lessons From Existing Models and Data.- Introducing Market Focus into Rate Design.- What Can We Learn From Customer Surveys.- IV. Supply Side Considerations.- Technical Foundations for Pricing Systems Security.- Optimizing Demand Side Contributions to Power System Security.- Design and Management of Curtailable Electricity Service to Reduce Annual Peaks.- V. Role of Enabling Technologies.- Utility and Customer Communication, Computing and Control (UC-3C) Technologies.- Integrated Utility Communications and Distribution Automation; Building the Framework for Differentiated Products.- VI. Utility Experience with Product Differentiation.- Reliability Service Options at PG&E.- Making the Transition: Prerequisites to Product Differentiation.- Priority Service and Outage Costs in the Power Sector: The Taiwan Perspective.- VII. Experience from Other Industries.- Parcel/Message Delivery Services.- VIII. Regulatory Perspective.- Are Reliability-Differentiated Products Unduly Discriminatory?.