The objective of this paper is to discuss the criteria for assessing geometric characteristics of manufactured parts, and the development of systematic procedures and algorithms for comparing measured geometric data from the manufactured parts (features) with specified design tolerances. Though the standards have used the concepts of the tolerance zones (TZs) and minimum zones (MZs) for evaluating different geometric (e.g. form, location, etc.) characteristics, the incompleteness in their definitions create ambiguities in implementing the inspection procedures in coordinate measuring machines (CMM). In this paper the concepts of TZ and MZ has been thoroughly investigated for establishing practical methodologies for part inspection.