  The expanding need for an open information sharing infrastructure to promote
scholarly communication led to the pioneering establishment of arXiv.org, now
maintained by the Cornell University Library. To be sustainable, the repository
requires careful, long term planning for services, management and funding. The
library is developing a sustainability model for arXiv.org, based on voluntary
contributions and the ongoing participation and support of 200 libraries and
research laboratories around the world. The sustainability initiative is based
on a membership model and builds on arXiv's technical, service, financial and
policy infrastructure. Five principles for sustainability drive development,
starting with deep integration into the scholarly community. Also key are a
clearly defined mandate and governance structure, a stable yet innovative
technology platform, systematic creation of content policies and strong
business planning strategies. Repositories like arXiv must consider usability
and life cycle alongside values and trends in scholarly communication. To
endure, they must also support and enhance their service by securing and
managing resources and demonstrating responsible stewardship.
