Abstract: A method and apparatus for cutting pattern pieces from sheet material with an automatically controlled cutting machine utilizes special control techniques for guiding a reciprocating cutting blade accurately along a desired cutting path defined by the pattern piece peripheries. The cutting machine includes a control computer which also serves as a data processor for generating machine command signals and controlling cutting blade movements. The controller has memory units which contain standard cutting programs and optinal programs. From a program selector panel, the cutting machine operator can select optional programs which modify the standard programs in a manner most suitably adapted to cause the cutting blade to follow the cutting path in the sheet material more accurately. The optional programs vary the feed rate or stroking speed, introduce yaw signals to control blade orientation along the cutting path, or perform other control functions.