We have a 'Conflict of Interest' section in our collections policy under Code of Ethics.  Here's a clause from that section:

" - collections shall not be made available to any individual on any basis for personal use, either on or off the premises or for any other purpose and contrary to the adopted collections policies"

Agree with everyone else that a strong collections policy is your best friend. 
tori

=========================================================
Important Subscriber Information:

The Museum-L FAQ file is located at http://www.finalchapter.com/museum-l-faq/ . You may obtain detailed information about the listserv commands by sending a one line e-mail message to [log in to unmask] . The body of the message should read "help" (without the quotes).

If you decide to leave Museum-L, please send a one line e-mail message to [log in to unmask] . The body of the message should read "Signoff Museum-L" (without the quotes).