The German ISIL Agency is part of the Staatsbibliothek zu Berlin (State Library of Berlin) and operates under the Department for Bibliographic Services.
The International Standard Identifier for Libraries and Related Organizations (ISIL, ISO 15511) is a globally recognized identification system for libraries and related organizations. This system integrates existing national and international identification systems to provide a unified framework.
Any institution requiring it for IT applications of any kind is eligible to obtain an ISIL.
German ISIL are valid only if they are listed as "active" in the official ISIL database. Any identifiers not included in the database or marked as "invalid" cannot be referred to or used as ISIL.
Typically, ISIL are assigned sequentially as numeric codes, although some may include letter combinations derived from previously assigned Sigel.
In Germany, ISIL for museums are managed by the Institut für Museumsforschung (IfM) at the Staatlich Museen zu Berlin. These identifiers are based on existing museum numbers from the national museum statistics and are submitted to the ISIL database of the Staatsbibliothek. ISIL only become valid upon publication in this database.
Each museum ISIL begins with "DE-" for Germany, followed by "MUS-" for museums, and the museum number.
ISIL with the prefix "ZDB-" are primarily used for electronic resource packages (virtual libraries). They facilitate metadata transfer within library networks.
These identifiers are also assigned to foreign libraries participating in the Zeitschriftendatenbank (ZDB) if their home country does not provide ISIL.
Example:
ZDB-LU-100 = Frauenbibliothek Cid-femmes, Luxemburg
Before ISIL, libraries in Germany used Sigel as national identifiers. This system originated in the early 20th century as part of the "Prussian Union Catalog" project and was further developed by the Royal Library in Berlin for reference and interlibrary loan.
Deutsche ISIL-Agentur - April 2015 (PDF)
„ISIL und die neue Adressdatei der ZDB“ gehalten von Andreas Heise auf der 16. Verbundkonferenz des GBV am 5. September 2012 in Hannover.
ISIL - Ein internationales Kennzeichen für Archive, Bibliotheken und Museen / Andreas M. Heise // In: Zeitungs-Mikrofilm-Nachrichten 14(2012)15, S. 4-6; zugleich in: Bibliotheksdienst 46(2012)11, S. 912-916
Bemerkungen über Sigelverzeichnisse und Bibliothekssigel anlässlich des 100. Geburtstags des früheren Auskunftsbüros der Deutschen Bibliotheken / Andreas M. Heise // In: Zeitschrift für Bibliothekswesen und Bibliographie (ZfBB) 51(2004)5/6, S. 305-31