The appts. forwards unanswered calls to a subscriber terminal in a dialling system. The appts. contains a device which first forwards calls when a predetermined number of calls following an operation at the terminal are unanswered, and only when no operation has taken place at the terminal since the first of these unanswered calls. Preferably, the appts. can forward calls when a call is not answered within a given time and when it is within a given period after the last unanswered call. The predetermined number of unanswered calls to trigger call forwarding can be one or more.
