A telephone conferencing system includes a voice services equipment (VSE) allowing a number of telephone calls to be connected together to form a conferencing function. Parties wishing to set up a conference agree on one of their telephone numbers being designated as a "link number". The conference participants dial into the system and then each enters the link number. The system stores the link number in a link number store when the first caller calls in. The system also checks the caller's calling line identity (CLI) with the entered link number, and the conference will not be enabled unless there is a match; thus, the conference cannot be initiated until the link number participant has called in. Any other participant calling earlier can be put on "hold". A number of different conferences may be taking place simultaneously, and participants will be grouped together correctly in their conference in accordance with the entered link number.