Integrated library system

An integrated library system (ILS), also known as a library management system (LMS), is an enterprise resource planning system for a library, used to track items owned, orders made, bills paid, and patrons who have borrowed.

An ILS is usually made up of a relational database, software to interact with that database, and two graphical user interfaces (one for patrons, one for staff). Most ILSes separate software functions into discrete programs called modules, each of them integrated with a unified interface. Examples of modules might include:

• acquisitions (ordering, receiving, and invoicing materials)
• cataloging (classifying and indexing materials)
• circulation (lending materials to patrons and receiving them back)
• serials (tracking magazine, journals, and newspaper holdings)
• online public access catalog or OPAC (public user interface)

Each patron and item has a unique ID in the database that allows the ILS to track its activity.