Over the past few years a number of new quality requirements have been released that have created some confusion in the dimensional metrology community. I have been asked many of the following questions, and I hope that these answers are useful to you and your organization. -JGS What is accreditation? Accreditation is the process of proving competency of calibration and testing services. In addition to management and quality systems requirements, accreditation demands proof of the technical ability of the calibration provider. The measurement capability of the calibration service is quantified using measurement uncertainty, which is a key requirement in accreditation. Accreditation also verifies that calibration procedures are appropriate and valid. Accreditation is therefore critical to ensuring traceability of measurements. What is measurement uncertainty? Measurement uncertainty is an estimation of potential errors in a particular measurement process. Uncertainty...