The requirements on gearing have steadily increased over the past years. On the one hand, increasingly more compact gear units with greater power density are required, while on the other hand high demands on operating behaviour and efficiency must often be met. All this means that gearing with top quality and low tolerance levels must be produced in both low and high volumes. Moreover, this gearing must often be produced with precisely defined flank modifications in order to achieve the desired characteristics. Gearing measurement technology has become a crucial aid in production, in order to create particular parameters and to ensure that they will be maintained during the manufacturing process. The design and functioning of appropriate testing machines will be described in the presentation. The conceptual design is explained in reference to the individual measuring tasks, and the most important components of the testing machine, such as drive systems, probe systems, control and computer systems are described. The second part of the presentation treats software as well as practical measurement examples in the areas of software management, operator guidance, evaluation and documentation of measurement results, examples of measurement times, measurement accuracy and the introduction of new software for the analytic evaluation of a gear set. By means of the gear contact analysis of a gear set, the combined effect of gear and pinion is simulated on the computer on the basis of individual profile and alignment measurements. Transactions on Engineering Sciences vol 23, © 1999 WIT Press, www.witpress.com, ISSN 1743-3533