This book presents the main methods and techniques for measuringand monitoring the accuracy of geometrical parameters of precisionComputer Numerically Controlled (CNC) and automated machines,including modern coordinate measuring machines (CMMs). Highlightsinclude:. Standard methods and means of testing, together with methodsnewly developed and tested by the authors;. Various parameters, such as straightness, perpendicularity, flatness,pitch, yaw, and roll, as well as the principal processes for measurementof these parameters;. Lists and tables of geometrical accuracy parameters, together withdiagrams of arrangements for their control and evaluation of measurementresults;. Special methods and some original new devices for measurementand monitoring, information measuring systems (consisting of laserinterferometers, photoelectric raster encoders or scales, etc.), andmethods for the measurement and testing of circular scales, lengthscales, and encoders;. Methods for measuring small lengths, gaps, and distances betweentwo surfaces;. Examples showing the suitability of mechatronic methods for highaccuracy correction of machines; and. Particular attention is given to the analysis of ISO written standardsof accuracy control, terms and definitions, and methods for evaluationof the measurement results during performance verification.