The following are some of the organizations and projects that are using handles for identifying digital objects.

The DOI System is an application of the Handle System to intellectual property. The DOI System is managed and developed by the International DOI Foundation, a not-for-profit membership organization. The DOI System adds to the Handle System an approach based on structured associated metadata; policies regarding scope and application; procedures for ensuring consistency and quality control across applications; business models; and specific application tools. Initial implementations are now being supplemented by increasingly sophisticated value-added tools for metadata management and content management, which will use the Handle System multiple resolution function. More information is available in the DOI^® Handbook.

The Advanced Distributed Learning (ADL) Initiative, managed by the Office of the Secretary of Defense Under Secretary of Defense for Readiness (DUSD/R), has started an effort to specify the Content Object Repository Discovery and Registration/Resolution Architecture (CORDRA). This effort will bring together existing standards and specifications in content management and network computing with the goal of greatly enhancing the reuse and interoperability of distributed learning content compatible with the sharable Content Object Reference Model (SCORM). One of the components selected for the project is CNRI's Handle System technology, for use in generating and resolving identifiers. This system was developed as part of CNRI's DARPA-funded Digital Object Architecture research, much of which is highly relevant to the CORDRA project. Specifically, CNRI will design a registration system for the ADL CORDRA project, to be known as the ADL Registry or ADL-R, and deliver it for use at the Defense Technical Information Center (DTIC). This effort will enable the discovery and reuse of learning content held in repositories distributed across the DoD.

The Defense Technical Information Center (DTIC), the Defense Advanced Research Projects Agency and CNRI are working on the Defense Virtual Information Architecture which focuses on applying CNRI's Digital Object Architecture and Handle System in combination with existing open standards, to develop a federated digital library system capable of disseminating metadata and data in a context sensitive manner. A prototype implementation of the DVIA, called the DVIA Registry, is currently accessible to DTIC users and CNRI only at http://hdl.handle.net/100.10/ALPHADVIA.

The DVIA Registry prototype demonstrates contextual linking by providing context sensitive Technical Report (TR) metadata search, navigation and access. The DVIA Registry resolves all requests and dynamically hyperlinks their results according to rules derived from the context of each request. All requests to the DVIA registry are expressed as OpenURLs which provide an open standard for describing context such as who is making the request, from where, how, to which service, and from which source and to what target. The combination of handles and OpenURL provide the necessary framework for enabling the DVIA Registry Contextual Linking Server to generate the appropriate contextual resolution in a location and server independent manner.

In the short term, DVIA system will build upon the architecture and expand the DVIA to encompass a wider variety of digital content and contextualization experiments. Further research and development will demonstrate the DVIA's ability to form extensible federation of distributed registries and the ability to extend on the functionality of the architecture by developing open contextualization rules.

The Handle System -- Globus Toolkit Integration Project leverages CNRI's Handle System technology through GT's Web services' protocols. The project will produce code and tools that will allow leverage of the Handle System technology through proxy-service interfaces that implement a Web services' front-end. Those proxy-services will enable implementation of the endpoints for protocols like the SAML attribute query exchange, the WSRF Service Group properties, XKMS, or a Renewable Endpoint Reference.

DSpace is a joint project of MIT Libraries and the Hewlett-Packard Company to provide stable, long-term storage to capture, preserve and communicate the intellectual output of MIT faculty, researchers, centers and labs. DSpace uses handles as persistent identifiers for the items stored.

The Library of Congress's National Digital Library Program is a broad based program to convert collections of historic materials to digital formats and to make them available across the Internet. CNRI is working with the Library of Congress to use handles to identify material in the library's own collections.