This text presents the basic system concepts while providing more detail and rigor than the conceptual descriptions found in many operation management texts. Mathematical decision models and tools for improving systems are described. In discussing production systems, the authors go beyond addressing the basic what questions, and provide guidance on how, when and why as well. While emphasizing planning models, the text delves into more hands-on engineering topics such as methods for setup time reduction, and fool proofing of production operations. The presentation follows the standard production system decision hierarchy. Modern philosophies such as time-based competition, lean manufacturing, and supply chain management are integrated into the discussion. This text presents a modern view of production system design and analysis at a level appropriate for upper division undergraduates and beginning graduate students in industrial engineering or quantitative business schools.