The Search Engine.BASE is one of the world's most voluminous search engines especially for academic open access web resources. BASE is operated by Bielefeld University Library.As the open access movement grows and prospers, more and more repository servers come into being which use the "Open Archives Initiative Protocol for Metadata Harvesting" (OAI-PMH) for providing their contents. BASE collects, normalises, and indexes these data. Our OAI-PHM-Blog communicates information related to harvesting and aggregating activities performed for BASE.BASE is a registered OAI service provider and contributed to the European project "Digital Repository Infrastructure Vision for European Research" (DRIVER) which was successfully completed at the end of 2009.