Safety first! If you're driving and an accident takes place in front of you, make sure you pull over to a safe area. Try to be far enough away from the accident to leave room for emergency vehicles, and to ensure that you're not in any danger. Next, put on your hazard lights. Only exit your car if it's safe. If you're on a busy highway, for example, it's probably best if you remain in your vehicle. And, if the cars involved are smoking, definitely keep your distance.
Call for backup. Every second counts in an emergency, so it's best to call 911 ASAP just in case someone is injured. Be prepared to describe the scene, and give your location. Again, make sure your car is in park before you use your cell phone.
Cautiously help out. If you feel it's safe to get closer to the scene of the accident, head over to see how you might be able to help, perhaps by offering your phone so the victims can call relatives or friends, or by setting up road flares to block off the accident area. If you see someone hurt, do not attempt to move them, since that could make their injuries worse. To ensure that those injured receive proper first aid treatment, wait for the authorities to arrive.
Stick around until the police arrive. You can help the authorities and those involved by giving an account of what you witnessed. Or, if someone is hurt or scared, you can act as a source of comfort until someone else arrives.
Tread carefully. In more tense situations, especially if someone was driving inappropriately or recklessly and caused the accident, the victim will benefit from you giving a statement to the police as a witness. Your presence might also help to defuse a possible argument between the drivers, or prevent someone from trying to leave the scene or take advantage of the other party. Just be mindful of your own safety, and try to stay calm.
How you act in those pivotal first few minutes after a car accident can have a meaningful impact on both the victims and the emergency response team. You can make big difference.