The Archivists' Toolkit version 1.5 has been released.
See "New Features for AT Release 1.5" for details.
Here's an excerpt from the home page that describes the software:
The Archivists' Toolkit™, or the AT, is the first open source archival data management system to provide broad, integrated support for the management of archives. It is intended for a wide range of archival repositories. The main goals of the AT are to support archival processing and production of access instruments, promote data standardization, promote efficiency, and lower training costs.
Currently, the application supports accessioning and describing archival materials; establishing names and subjects associated with archival materials, including the names of donors; managing locations for the materials; and exporting EAD finding aids, MARCXML records, and METS, MODS and Dublin Core records. Future functionality will be built to support repository user/resource use information, appraisal for archival materials, expressing and managing rights information, and interoperability with user authentication systems.