When you say it’s another library in the same system, do you mean something like a different branch of the same city or county library? "Systems" can mean different things to different groups of libraries. In some cases, "systems" can be very loosely-organized groups or very centralized organizations throughout a region. The more closely organized a system is (like a city or county system), the more likely they’re going to have a delivery system that can get items returned between branches/libraries.

Still, most libraries have some way to make sure that books delivered to the wrong location get sent back to the right place, so having them be completely lost isn’t all that common. However, it does happen.

Your best bet is to talk to the library where you borrowed the book from. They may be able to mark your record with a "claimed returned" status, or something similar. Depending on just how your library handles such things, you may or may not have to pay a fine. It’s a very local decision, so you really do need to talk to them directly.

Hope this is helpful!

–Bill Pardue
Arlington Heights Memorial Library
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