Laser trackers are precision measurement devices often used to measure parts too large for conventional Coordinate Measuring Machines (CMMs). Multiple laser trackers can be used simultaneously to increase the number of part features viewable and therefore available for measurement. Each laser tracker has its own coordinate system that is linked to the others through the measurement of common points. The process of registration uses these common points to bring all measurement data into a Common Coordinate System (CCS). Provided all measurements are in a CSS, any localized part feature measured by more than one laser tracker can benefit from sensor fusion. This process improves the measurement accuracy of a feature location by using the error information associated with each laser tracker. This paper describes the application of sensor fusion and registration algorithms to metrology. Testing of the registration and fusion algorithms is performed using an API laser tracker 2. The algorithms are being commercially implemented in the Maya Metrix Build!IT software.