A collaborative effort of the Networked Digital Library of Theses and Dissertations (NDLTD), OCLC, VTLS, and Scirus, the NDLTD Union Catalog contains more than one million records of electronic theses and dissertations. For students and researchers, the Union Catalog makes individual collections of NDLTD member institutions and consortia appear as one seamless digital library of electronic theses and dissertations.

In addition to the 75.000 prints belonging to the basic content, VD16 comprises a supplement of more than 25.000 new titles. New titles are added continuously through acquisitions by the Bayerische Staatsbibliothek for the Collection of German Prints, as well as through data provided by national and foreign libraries.