The most recent analysis pegs the total cost of keeping one book in an open library stack (the kind that allows browsing) at $4.26 per year (in 2009 dollars). High-density shelving, a less costly alternative to open stacks, comes at $.86 per book, per year (again, in 2009 dollars).

And given the costs, academic financial officers blanch at proposals to build new on-campus storage capacity for thousands, in some cases millions, of books.

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An increasingly popular strategy for managing overcrowded stacks is moving books to high-density, low-cost, off-campus storage.

This too can be met with resistance from faculty and students. For example, at Syracuse University, faculty reacted with with what was described as “fury” when campus librarians planned to move low-use books to an off-campus storage facility.

Even so, the practice has become routine for many academic libraries. As of 2014, an estimated 75 high-density academic library storage facilities have been built in the US.

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Academic librarians have formed a task force to investigate the creation of a distributed shared monograph archive on behalf of HathiTrust, a shared digital preservation repository containing the scans of millions of printed books belonging to a coalition of academic libraries.

The proposed HathiTrust monograph archive will allow those same academic libraries to reduce the footprint of their on-campus collections by relying on shared archival copies of low-use, mostly public domain books whose full texts are available digitally via HathiTrust.