Abstract: The invention relates to call waiting started by a calling subscriber (subscriber A) on the busy line of a called subscriber (subscriber B). The calling subscriber starts the call setup to the called subscriber, whereby a call setup message is sent to the called subscriber. According to the invention, the call waiting method is characterized in that such a call waiting setting is set for the call to be set up with which call waiting is activated and a call priority value is set which expresses the urgency of the call, and the said call waiting setting and the said priority value are relayed to the called subscriber in connection with the call setup.