Teaching members of the public how to recognise and respond to life-threatening injuries after a road traffic collision can save lives, and simple tools such as the sBATT score show that serious trauma can often be identified using visible clues, such as confusion, heavy bleeding, fast breathing, or being trapped in a vehicle, without the need for medical equipment. Early evidence suggests that bystanders can sometimes recognise critical problems such as airway issues, bleeding, or hypothermia, but they often underestimate how severe bleeding is and may struggle to judge how urgently help is needed. Many other signs, including changes in alertness, heart rate, or breathing, could potentially support emergency responders, though it remains unclear whether bystanders can reliably assess them. As new approaches such as community training, telemedicine support, and digital tools become more common, further research is needed to understand which methods most effectively teach and support bystanders to provide first aid after road traffic collisions, and how best to measure the benefits of these approaches in real-world situations.