An annunciation method comprising: foreseeing a potential collision risk between a vehicle and a potential traffic participant predicted to be present ahead in a direction of travel of the vehicle; performing a first annunciation notifying those in a vicinity that the vehicle is traveling, using an externally-directed annunciator installed in the vehicle, in response to the potential collision risk being foreseen; sensing a manifested collision risk between the vehicle and a manifested traffic participant of which presence is confirmed ahead in the direction of travel of the vehicle; performing a second annunciation notifying those in the vicinity regarding collision avoidance actions of the vehicle, using the externally-directed annunciator, in response to the manifested collision risk being sensed; wherein the externally-directed annunciator includes at least one display panel which is attached to at least one face of the vehicle; the method further comprising prioritizing the first annunciation over the second annunciation as long as the potential collision risk continues, the method being characterized in that when the first annunciation is prioritized, "passing" or "starting to move" is displayed as the first annunciation on the at least one display panel; and when the first annunciation is not prioritized, the second annunciation is performed and "decelerating" or "yielding" is displayed, as the second annunciation, instead on the at least one display panel. foreseeing a potential collision risk between a vehicle and a potential traffic participant predicted to be present ahead in a direction of travel of the vehicle; performing a first annunciation notifying those in a vicinity that the vehicle is traveling, using an externally-directed annunciator installed in the vehicle, in response to the potential collision risk being foreseen; sensing a manifested collision risk between the vehicle and a manifested traffic participant of which presence is confirmed ahead in the direction of travel of the vehicle; performing a second annunciation notifying those in the vicinity regarding collision avoidance actions of the vehicle, using the externally-directed annunciator, in response to the manifested collision risk being sensed; wherein the externally-directed annunciator includes at least one display panel which is attached to at least one face of the vehicle; the method further comprising prioritizing the first annunciation over the second annunciation as long as the potential collision risk continues, the method being characterized in that when the first annunciation is prioritized, "passing" or "starting to move" is displayed as the first annunciation on the at least one display panel; and when the first annunciation is not prioritized, the second annunciation is performed and "decelerating" or "yielding" is displayed, as the second annunciation, instead on the at least one display panel. prioritizing the first annunciation over the second annunciation as long as the potential collision risk continues, the method being characterized in that when the first annunciation is prioritized, "passing" or "starting to move" is displayed as the first annunciation on the at least one display panel; and when the first annunciation is not prioritized, the second annunciation is performed and "decelerating" or "yielding" is displayed, as the second annunciation, instead on the at least one display panel.