This publication addresses standardization and certification issues of general industry interest. The book sets out the fundamental provisions of the state standardization system, provides general technical standards, rules and requirements for groups of homogeneous engineering products. A separate section of the publication is devoted to the problems of standardization and interchangeability, a system of tolerances and fits is given, including for various types of connections, gears, plastic products. Particular attention is paid to the issues of assigning tolerances on dimensions and the location of the surfaces of product parts based on the methods of dimension chains. Describes methods for calculating linear, angular, and vector dimension chains.