Abstract: A telephone system having a telephone network line for connection to an external phone line. The telephone system also includes a computer system and a telephone coupled to the telephone network line, and the telephone is taken off-hook to enter a voice command. A transmitter communicates the voice command from the telephone to the computer system without the telephone seizing the external phone line. A computer interface unit is connected to the computer system to receive the voice transmitted from the telephone and to transmit voice signals transmitted by the computer system to the telephone. A phone interface unit is connected between the telephone and telephone network line, and the phone interface unit is selectable between a first mode and a second mode. The phone interface unit connects the telephone to the telephone network line if it is in the first mode, and isolates the telephone from the telephone network line if it is in the second mode.