Libraries all over the world have to deal with fast growing numbers of digital materials that need to be safeguarded. Publications in digital form, online or on CD, digitised images, and born-digital objects need to be preserved and kept accessible. Safeguarding digital heritage is a major issue, especially for national libraries, because of their legal task of preserving the national heritage of a country. This volume describes the state of the art of digital repositories, preservation strategies and current projects in the national libraries of Australia, Austria, Canada, China, Denmark, France, Germany, Japan, Netherlands, New Zealand, Portugal, Sweden, Switzerland, the UK and the USA.