Large gears have become an indispensable part of modern technical applications. The expanding industrial sectors of power generation and transmission@ like shipbuilding industry@ wind turbine generators and petroleum conveying systems@ have led to an increasing demand for large scale gear boxes. Thus@ the qualified measurement of large gears has become more and more important as well. Their conformance with specifications according to ISO 14253-1 [1] has to be proved@ which is not possible without a qualified statement of the task-specific measurement uncertainty. As a consequence@ the manufacturing processes cannot be controlled quantitatively and at a reasonable process capability level@ especially if tolerances are small compared to the achievable measurement uncertainty. This specifically applies to large gears. In this report three current projects are outlined and presented with a comparison for large involute gears. The measurement results are presented. As a second step towards traceable measurements of large gears@ a special calibration laboratory shall be established. This is part of a joint research project@ within which also a new measurement standard of 2 m in diameter has been developed. Lastly@ information about a Joint Research Project within the European Metrology Research Program which will start in September 2014 is provided.