The invention concerns a transmission method in a communication system comprising a communication system between a subscriber equipped with a telecommunication station (1) and an emergency center (9) responsible for collecting necessary data, and for organizing rescue operations, said emergency center being capable of transmitting and of receiving voice calls, said communication system being managed by an operator (7). When the subscriber calls the emergency center (9), the system transmits to said emergency center (9), via the operator (7), in addition to or instead of a voice message transmitted by the subscriber, at least one non-voice supplementary data, said supplementary data including at least the exact location of the subscriber.