Abstract: A trunking protocol for a two-way radio communication system designates an available channel as a parking channel for radios on standby. The parking channel is converted to an active voice channel upon request for a voice call, and non-called radios are then moved from the newly-designated voice channel to a newly-designated parking channel. Upon completion of the voice call, the participating radios are moved to the then-existing parking channel, and the channel of the just-completed voice call becomes available. If all channels are busy such that no parking channel is available, the radios in standby mode convert to operate in scan mode until a channel becomes available to serve as the parking channel.