In 2005 the Bibliotheca Rosenthaliana celebrated its 125th year as part of the University Library of the University of Amsterdam. Several events were held to mark this anniversary, including lectures and an exhibition. In this volume the history of the library is examined further with new and incisive articles on the life and work of many of its leading figures and an analysis of part of Leeser Rosenthal's original collection. In addition, new material is presented regarding the fate of the library during the Second World War. A year earlier, in 2004, Adri Offenberg retired as curator of the Bibliotheca Rosenthaliana. Alongside a review of his work at the library, this volume provides a complete bibliography of all his published work until 2006 and what has become known in English as a festschrift: a collection of studies in his honour by Dutch and international colleagues and fellow bibliophiles about items in the library collection, as well as topics relating to Jewish booklore unconnected with the library. This volume is a tribute to Adri Offenberg the curator, but above all to Adri Offenberg the groundbreaking researcher.