Here is a new guidelines document published online today by the Rare Book and Manuscripts Section, IFLA (International Federation of Library Associations).
From a Blurb:
Digitization guidelines have proliferated in many forms over the last fifteen years, and all of them reflect a set of best practices that continues to evolve. These guidelines attempt to complement this body of knowledge by addressing the specific needs related to planning digitization projects for rare and special collections. They are written from the point-of-view of special collection managers, rare book librarians, curators, and researchers who study the physical object as an artefact bearing intrinsic historical evidence as much as for the intellectual content that it contains. Foreshadowing the needs of users who are now conducting digital-based research that requires full-text analysis or large aggregations of “big data,” these guidelines will also help professionals and non-professionals create sustainable and adaptable digital collections that will be re-useable and continue to have research value into the future.