The Music Collection at the Diocesan Library in Sandomierz is one of the most valuable and extensive of this kind in Poland. It includes in total 807 library items (many collections among them) described in 2522 catalog records. Vast majority of the manuscripts originates from the eighteenth century, a significant number from the first three decades of the nineteenth century and single copies from the seventeenth century. Volume 1 of the Catalog (1550 records), preceded by an extensive introduction, encompasses the repertoire of the church ensembles (vocal-instrumental and chamber music) and keyboard compositions. In preserved manuscripts there are mainly compositions of Polish, Italian, German, and Czech composers however anonymous compositions prevail.The Catalog of music manuscripts from Sandomierz was created in cooperation of musicologists from Adam Mickiewicz University in Poznan and the RISM Catalog of Musical Sources with its Editorial Office in Frankfurt am Main.