Injection molding continues to be a core plastics manufacturing process, but now has competition from additive manufacturing for certain applications, and environmental concerns are in the spotlight. The 3rd edition addresses these issues, in particular with a new chapter on mold manufacturing strategy to provide an overview of the most common machining and additive manufacturing processes with cost and time models to guide the manufacturing strategy; updated and simplified break-even cost models to assist in the mold layout design (number of cavities and type of mold) vs. 3D printing; a new section on environmental concerns include mold design for recycled resins; and updates to the International Tolerance standards, and the new technology and simulation sections.