A device for providing teleconference capabilities in an ISDN includes a first receiver for receiving a first signal representing a first message over a first ISDN B-channel. A second receiver receives a second signal representing a second message over a second ISDN B-channel. A receive mixer mixes the first signal with the second signal to produce a receive mixed signal. A local receiver receives a local signal representing a local message to be transmitted over the first and second ISDN B-channel. A first transmit mixer mixes the first signal with the local signal to produce a first transmit mixed signal. A first transmitter transmits the first transmit mixed signal over the second ISDN B-channel. A second transmit mixer mixes the second signal with the local signal to produce a second transmit mixed signal. A second transmitter transmits the second transmit mixed signal over the first ISDN B-channel.