PAM Anticipative Manufacturing is a whole new way of doing CAM. It is based on 2 principles: adaptive allowance and constant tool engagement.  The roughing cycle anticipates and prepares finishing by leaving an adaptive allowance, thus enabling constant tool engagement for finishing.  What you get with PAM:  Constant effort on the tool all throughout the machining cycle Larger Z step values can be used Vibrations are eliminated Results: Shorter machining time Extended tool life Higher surface quality