This document describes principles and tools to control a manufacturing process in accordance with a GPS specification. For this purpose it is necessary to use a set of one or more complementary, independent characteristics that correlate to the manufacturing process parameters. This document describes the concept of decomposition of the macro-geometrical part of the GPS specification. It does not cover the micro-geometry, i.e. surface texture. The objective of the decomposition presented in this document is to define correction values for manufacturing control or to perform a statistical analysis of the process.