This wiki about PV metrology was initiated by Dr. Stefan Winter, Dorothea-Erxleben-Str. 45, 38116 Braunschweig, Germany, E-Mail Winter@pvmet.org. It will be extended and maintained as part of the EMPIR project Metro-PV by publishing research results from this project and its predecessors PV-Enerate and PhotoClass for a broader community. But we also welcome and need contributions from PV metrologists worldwide. Our mission is to create a comprehensive knowledge pool for the area of PV metrology.