This book provides a structured methodology and scientific basis for engineering injection molds. The topics are presented in a top-down manner, beginning with introductory definitions and the big picture before proceeding to layout and detailed design of molds. The book provides very pragmatic analysis with worked examples that can be readily adapted to real-world product design applications. It will help students and practitioners to understand the inner workings of injection molds and encourage them to think outside the box in developing innovative and highly functional mold designs. This new edition has been extensively revised with new content that includes more than 80 new and revised figures and tables, coverage of development strategy, 3D printing, in-mold sensors, and practical worksheets, as well as a completely new chapter on the mold commissioning process, part approval, and mold maintenance.