Introduction

The preservation of digital resources is about finding ways to maintain our digital heritage, whether it exists in the form of e-journals, database records, Web sites, emails, digital images, audio-visual materials, interactive programs, or any other kind of binary data. Libraries frequently engage with a wide variety of these resources and understand how quickly and easily we lose use of them when computers change or links break.

I have been privileged to work in national libraries for nine years, devoting my time solely to the task of digital preservation. In that time many different solutions have been proposed, and as many opinions have been voiced about whether these solutions will work. While it is often perceived that these opinions contradict or argue with each other, the real answer is in finding the balance of what works in a particular situation. I hope that through this issue of Library Trends we may start to see how each solution has its own benefit in a particular context.

All the articles in this issue agree on the challenges of digital preservation: the burgeoning volumes of digital resources to be dealt with; the temporary nature of digital materials, particularly the rapid changes in their formats; and the massive organizational revolution required to work with and preserve digital materials, including the associated costs. However, the context in which digital preservation challenges apply is a highly important factor in making the right choice of a solution. For example, the context of the data can change its meaning and use. The context of the resource can change its relevance and integrity. The context of a collection in an organization can impact its value, and the context of a collecting organization can affect legal rights and obligations for digital preservation.

The articles in this issue illustrate a variety of solutions in a range of contexts, from the implementation of large systems to issue-specific solutions that are still in development. The first three articles feature large-scale digital preservation storage systems being built in three different environments: an academic library, a national library, and a media organization. We can see similar issues arise in each story but with different details that impact the solutions chosen. The interesting contrast here is largely affected by legal rights and responsibilities.

The heterogeneity of digital materials being collected increases complexity in systems and solutions, as shown in the first article by MacKenzie Smith, who describes the development of DSpace at MIT. A significant lesson illustrated by DSpace is that complex systems benefit from an incremental building approach such as spiral development.

Cathy Smith describes the imperatives of the British Broadcasting Corporation (BBC) as a British media body and explores the responsibilities of organizations other than libraries to provide preservation and access to digital information. Developing trust and cooperation with organizations such as the BBC may ease the burden on libraries and archives to be the sole keepers of digital information.

The article by Johan Steenbakkers exemplifies the commitment of national libraries around the world to solving the difficulties of digital preservation. The Koninklijke Bibliotheek (KB), or National Library of the Netherlands, has provided strong leadership and innovation in digital preservation issues. Johan explores the impermanence of digital library collections and the new roles and responsibilities of digital publishing, in particular scientific journal publishers. The KB has been at the forefront of archiving system development and looking for practical preservation strategies by engaging with commercial research partners to try to encourage widely available and supported solutions. Part of this is a strong commitment to sharing and cooperation.

The focus of the issue then moves on to selection and acquisition of digital resources for preservation. Publishing models have changed radically, and the Internet provides an easy conduit for the proliferation of digital information; therefore libraries are faced with divining new and manageable methods of finding, selecting, and acquiring resources for their collections. Libraries often license or link to material online rather than store it locally, so it is no longer acceptable, legal, or even possible to passively keep digital publications in a collection.

Two articles in this issue present examples of a variety of...