Abstract: An encrypted multimedia streams transceiving method between a first and second user, includes using a device for transceiving multimedia streams connected to a respective electronic computer by both users; the method including a step of preventive activation of a free-to-air communication session between the users through a software for making multimedia communications within which the device operates in a first free-to-air transmission configuration, a step of creating an encrypted communication, within which the device operates in a second encrypted transceiving configuration; a step wherein the device causes the opening of a session for the transfer of encrypted data between the electronic computers, different from the free-to-air communication session used by the software for making calls, and at least audio data stream transceived between the two users during their communication is selectively switched between the free-to-air communication session and the encrypted data transfer session on the basis of a