Improvements in computing and network technologies, digital data capture, and data mining techniques are enabling research methods that are highly collaborative, network-based, and data-intensive. These methods challenge existing scholarly communication mechanisms, which are largely based on physical (paper, ink, and voice) rather than digital technologies.

One major challenge to the existing system is the change in the nature of the unit of scholarly communication. In the established scholarly communication system, the dominant communication units are journals and their contained articles. This established system generally fails to deal with other types of research results in the sciences and humanities, including datasets, simulations, software, dynamic knowledge representations, annotations, and aggregates thereof, all of which should be considered units of scholarly communication.¹

Another challenge is the increasing importance of machine agents (e.g., web crawlers, data mining applications) as consumers of scholarly materials. The established system by and large targets human consumers. However, all communication units (including the journal publications) should be available as source materials for machine-based applications that mine, interpret, and visualize these materials to generate new units of communication and new knowledge.

Yet another challenge to the existing system lies in the changing nature of the social activity that is scholarly communication. Increasingly, this social activity extends beyond traditional journals and conference proceedings, and even beyond more recent phenomena such as preprint systems, institutional repositories, and dataset repositories. It now includes less formal and more dynamic communication such as blogging. Scholarly communication is suddenly all over the web, both in traditional publication portals and in new social networking venues, and is interlinked with the broader social network of the web. Dealing adequately with this communication revolution requires fundamental changes in the scholarly communication system.

Many of the required changes in response to these challenges are of a socio-cultural nature and relate directly to the question of what constitutes the scholarly record in this new environment. This raises the fundamental issue of how the crucial functions of scholarly communication ² – registration, certification, awareness, archiving, rewarding – should be re-implemented in the new context. The solutions to these socio-cultural questions rely in part on the development of basic technical infrastructure to support an innately digital scholarly communication system.

This paper describes the work of the Object Re-Use and Exchange (ORE) project of the Open Archives Initiative (OAI) to develop one component of this new infrastructure in order to support the revolutionized scholarly communication paradigm – standards to facilitate discovery, use and re-use of new types of compound scholarly communication units by networked services and applications. Compound units are aggregations of distinct information units that, when combined, form a logical whole. Some examples of these are a digitized book that is an aggregation of chapters, where each chapter is an aggregation of scanned pages, and a scholarly publication that is an aggregation of text and supporting materials such as datasets, software tools, and video recordings of an experiment. The ORE work aims to develop mechanisms for representing and referencing compound information units in a machine-readable manner that is independent of both the actual content of the information unit and nature of the re-using application.