Free-form machining is one of the most commonly used manufacturing processes by several industries, such as automotive, aerospace, die and mold. It is critical, but often difficult, to select applicable cutting conditions to achieve high productivity while maintaining high quality of parts. It is essential to optimize the feedrate to improve the machining efficiency. Conservative constant feedrate values have been mostly used up to now because of lack of physical models and optimization tools. Commonly used CAM programs are based on the geometric and volumetric analysis, but they do not concern the physics of the free-form machining process. The new approach introduced in this book is based on the mechanics of the process. The cutting force based models in which feedrate is set to values which keep either average or instantaneous machining forces to prescribed values. In this book, both feedrate scheduling strategies are compared theoretically and experimentally for ball-end milling of free-form surfaces. A new mathematical model is also introduced for predicting the form errors which affect the surface quality and productivity in free form machining with ball-end milling.