US Patent 7606558 Key control with real time communications to remote locations

A key control system includes at least one premise, a lockbox capable of securing a key to the premise and at least one mobile telephone associated with a user and having a stored access device program capable of communicating an access request to the lockbox. The premise is subject to authorized access by others, such as the user, based on preferences of an approval party established with the system. If specified by these preferences, the mobile telephone automatically initiates a communication to a selected destination to request approval of the access request.