A trusted digital repository is one whose mission is to provide reliable, long-term access to managed digital resources to its designated community, now and in the future. Trusted digital repositories may take different forms: some institutions may choose to build local repositories while others may choose to manage the logical and intellectual aspects of a repository while contracting with a third-party provider for its storage and maintenance. Whatever the overall infrastructure, however, to meet expectations all trusted digital repositories must · accept responsibility for the long-term maintenance of digital resources on behalf of its depositors and for the benefit of current and future users; · have an organizational system that supports not only long-term viability of the repository, but also the digital information for which it has responsibility; · demonstrate fiscal responsibility and sustainability; · design its system(s) in accordance with commonly accepted conventions and standards to ensure the ongoing management, access, and security of materials deposited within it; · establish methodologies for system evaluation that meet community expectations of trustworthiness; · be depended upon to carry out its long-term responsibilities to depositors and users openly and explicitly; · have policies, practices, and performance that can be audited and measured; and Example : - A large university library with a growing collection of digital materials to support teaching and research, including online databases, electronic journals, digitized materials, digital output of university staff and students (e.g., theses and dissertations), digital course materials, and institutional records in electronic form. This repository serves primarily the university’s faculty, staff, and students, but secondary users include the wider academic community and local community members who purchase library privileges. The university assumes that researchers will have access to the digital collections on campus via the local area network or via the Internet using the high-speed academic network and a personal computer. Descriptive access to the collections is available through the library management system and all access privileges are controlled by a user authentication system in order to meet licensing and intellectual property rights arrangements. The producer/creator community for the university library, like the national library, may include almost anyone, from an individual scholar to a large commercial publisher. Locally, the university will have some control over the creation of digital materials, but most come from producers over whom the library exercises little or no influence. The university computer service is contracted to host the digital repository. The system, currently under review, is based on the OAIS (Open Archival Information System) Reference Model.