The design of extrusion forming tools (dies and calibrators) is a difficult task usually performed by the employment of experimental trial-and-error procedures, which can hinder the performance and cost of the tools, may increase the time to market of new extruded products and limit their complexity. The main objective of this book is to provide detailed information on the design of extrusion forming tools. It describes the main problems to be faced when designing dies and calibrators, the most relevant polymer properties to be considered in the design process, the specific problems related to several types of conventional extrusion dies, and recent developments on the design of special dies and process modelling. It will be an updated and uncommon book on the subject, where each chapter is prepared by internationally recognised experts. Having in mind its nature, it is expected to become a useful reference book for higher education students (both undergraduate and graduate ones), teachers, researchers and engineers active in the extrusion industry.