One thing that many museums deal with is the issue of reproductions in the collection.
For example: Yesterday I was going over an accession list for one of our collections (the list that was made of everything when it came into the museum). One of the items on the list was a bust by
Desiderio da Settignano. I was skeptical. I doubted that we had a marble bust from an Italian Renaissance sculptor in the collection. But it's possible. Our collection, while small, is very diverse.
I hadn't encountered the object before, so I went to check on it. As I lifted it out of the back corner of the shelf it was on, I knew that it wasn't an original (it was far too light to be marble, and the inside was hollow); it was a plaster reproduction of
A Little Boy.

Interestingly, none of the written documentation had indicated that this object was a reproduction. It was also mis-identified as a bust of the infant Christ. But a few minutes using google identified the original as residing in the National Gallery, and not being of an infant Christ, but an anonymous boy.
Now it's properly identified, and we have an issue in front of us: what do we do with this reproduction? It's not the real object, so it doesn't have the same intrinsic value (and I'm not referring to monetary value - the same would be true of a reproduction of a military uniform, or of a cereal box, for that matter) that the original would have. So do we keep it? If we don't keep it, what do we do with it?
I have my thoughts on this matter, but I'm going to keep them to myself. What do you think? How should museums handle reproductions (fakes) in their collections?