We are looking for ideas to help users search our collections for photos
based on concepts (e.g. diversity) rather than the subject matter depicted
in the photo. Since the high priority institutional objectives are often
behind requests for these items, we'd really like a better solution than
telling them to go fishing.

Concepts that are not part of the subject matter are subjective and
contextual by nature, but we can identify photos that satisfy some of the
more common requests. However, we have not come up with a way to add
appropriate access points -- methods that come to mind would/should get
anyone involved tarred, feathered, and run out of town on a rail.

Parenthetical qualifiers work reasonably well for some concepts and visual
elements not directly related to the actual subject matter in a photo. But
this method doesn't work for sensitive topics.

Has anyone come up with a good way to provide this sort of access? Thanks,