A system for providing telephony and data services to a user's premises, the system comprising: a termination unit for terminating an incoming pair of conductors (11, 12) from a telecommunications access network within the user's premises, the termination unit having a connector portion operable to connect with a corresponding termination unit to modem connector containing three conductors able to carry electrical signals, the termination unit being arranged to provide a good electrical connection between two of the conductors (232, 235) within the termination unit to modem connector, which conductors, when in use, carry data signals between the access network and a user modem and are hereinafter referred to as the two data carrying conductors, and the incoming pair of conductors (11, 12) from the access network respectively, wherein the termination unit is operable to provide an insulation of the other of the three conductors within the connector from the incoming pair of conductors (11, 12) from the access network; the system further comprising a user modem which is connectable to the termination unit to modem connector and is operable to transmit data signals onto and to receive data signals from the data carrying conductors (232, 235) and is further operable to transmit telephony signals onto and to receive telephony signals from a pair of modem-side telephony signal carrying conductors which includes the other conductor within the termination unit to modem connector and one of the data carrying conductors within the termination unit to modem connector, whereby the pair of data carrying conductors (232, 235) and the pair of modem-side telephony signal carrying conductors (233, 235) within the termination unit to modem connector share a common conductor; and the system further comprising a cross-connection unit having a connection portion which is operable to connect with a telephone connector, which telephone connector includes at least two telephone-side telephony signal carrying conductors (45, 46) operable to carry telephony signals to and from a telephone apparatus 50, the cross connection unit 40 further including a cross-connection (245, 243) which electrically connects the two telephone-side telephony signal carrying conductors (45, 46) to the two modem-side telephony signal carrying conductors (233, 235) respectively when in use. a termination unit for terminating an incoming pair of conductors (11, 12) from a telecommunications access network within the user's premises, the termination unit having a connector portion operable to connect with a corresponding termination unit to modem connector containing three conductors able to carry electrical signals, the termination unit being arranged to provide a good electrical connection between two of the conductors (232, 235) within the termination unit to modem connector, which conductors, when in use, carry data signals between the access network and a user modem and are hereinafter referred to as the two data carrying conductors, and the incoming pair of conductors (11, 12) from the access network respectively, wherein the termination unit is operable to provide an insulation of the other of the three conductors within the connector from the incoming pair of conductors (11, 12) from the access network; the system further comprising a user modem which is connectable to the termination unit to modem connector and is operable to transmit data signals onto and to receive data signals from the data carrying conductors (232, 235) and is further operable to transmit telephony signals onto and to receive telephony signals from a pair of modem-side telephony signal carrying conductors which includes the other conductor within the termination unit to modem connector and one of the data carrying conductors within the termination unit to modem connector, whereby the pair of data carrying conductors (232, 235) and the pair of modem-side telephony signal carrying conductors (233, 235) within the termination unit to modem connector share a common conductor; and the system further comprising a cross-connection unit having a connection portion which is operable to connect with a telephone connector, which telephone connector includes at least two telephone-side telephony signal carrying conductors (45, 46) operable to carry telephony signals to and from a telephone apparatus 50, the cross connection unit 40 further including a cross-connection (245, 243) which electrically connects the two telephone-side telephony signal carrying conductors (45, 46) to the two modem-side telephony signal carrying conductors (233, 235) respectively when in use.