> Has anyone been able to give a projection to their management on what the > total cost per TB is for preservation over even a short horizon of 10 years? The trick is that the cost varies drastically with the model employed. Preservation is insurance, plain and simple. If you buy more coverage, you're protected against a wider variety of threats. The problem with most preservation discussions is that options are weighed only in the abstract. The best protection consumes significant financial and staff resources -- which reduces your ability to deliver services. Plus, there is no such thing as removing all risk. The most appropriate model for an institution will vary depending on what they need to preserve, how much there is, and how they define acceptable risk. It's all a matter of defining where the lines are drawn. There is a tendency to pretend that analog libraries are somehow safe, but even if theft/loss weren't issues, they get flooded and catch fire. In the bad 'ol days, catalog drawers could be burned in protests, and in contemporary times, loss of vendor support for your system or other problems represent a real threat. kyle