A preemptive telecommunication interface is provided with a microprocessor, non-volatile storage media containing a database, and software. The microprocessor is capable of reading incoming signals designating telephone numbers from the telephone company. The microprocessor is further capable of comparing an incoming telephone number to an authorized list of telephone numbers kept in the database. If an incoming telephone number is among those authorized, the telephone call is "answered" and a telecommunication line is connected to a main computer system or facsimile machine. If the incoming telephone number is not among those authorized, the telephone call is "preempted" (i.e., not answered).