From around the 1990s, the concept of digital archives became increasingly popular both in Japan and overseas, and many digital archives are currently being built in museums, libraries, or educational institutions. At the same time, digital archives are facing various challenges, that lead to many not being sustainable and disappearing after a while. This paper outlines "organizational issues" and "systemic issues" which are commonly regarded as major reasons for the disappearance of digital archives and discusses ways to make counteract these problems and make digital archives more sustainable.

In the aftermath of the Great East Japan Earthquake, any number of archives were established to preserve records of the disaster. Now, more than 10 years since the disaster struck, difficulties related to maintenance and operation have caused many of these archives to close. In order to ensure that this content remains available to the public, the National Diet Library has taken over materials from many closed archives, but in doing so has had to deal with a variety of issues, such as handling the rights associated with the content. This paper discusses the closure of these archives and the challenges associated with acquiring their content.

Biodiversity information represents natural history data. We discussed issues related to the accumulation and long-term use of basic information associated with specimens. The National Museum of Nature and Science has the "Collection Databases of Specimens and Materials" for in-house data management and the "Science Museum Net (S-Net)" for the accumulation of data from other domestic natural history museums. We compared these two systems in terms of implementation, issues involved in long-term storage and use of data, specifications, long-term maintenance and assurance of the systems, and data format and data transfer. In the future, it will be important to have trained personnel who can evaluate external collaboration, security, etc., and share know-how on system construction in addition to these perspectives.

This paper describes the four perspectives of 'Collaboration', 'Human resources', 'Update' and 'Utilization', which are important for the sustainability of digital archives, based on ADEAC's work. The 'Collaboration' describes ADEAC's concept and the importance of working together as one. 'Human Resources' describes our training courses for digital archivists and the importance of information literacy. 'Update' describes cases that demonstrate its effectiveness and expectations for the virtuous circle created by the new improved version of ADEAC. 'Utilization' describes how the digital archive will become an essential knowledge base for the region through the practical use of digital archives as learning materials in schools. The sustainability of digital archives will be enhanced by the continuation of these activities, which will lead to the avoidance of their disappearance.

In recent years, digital archives have been compiled at various institutions and companies. However, there are cases without sufficient consideration for its continuity, so that the amount of access have beed decreased, or reconstruction may be needed. This paper provides specific recommendations on how to address this issue from the preparatory stage of digital archiving to post-construction, from the five perspectives, i.e., metadata, digital archiving systems, operation, and public relations and human resource development.