The Forschungsdatenzentren aims to facilitate the use of de-personalized microdata in science. For the use in Forschungsdatenzentren, a chosen set of statistics are processed sequentially and then their metadata are documented. The FDZ-Metadatensystem Online is presently under construction and belongs to the Forschungdatenszentren of the Official Statistics. All the metadata for which microdata are available in the Forschungsdatenzentren will be made available in Internet in the future by this system. www.forschungsdatenzentrum.de