A first responder is an umbrella term for the first medically trained person to arrive on the scene of a medical emergency, accident, or other issue of public safety, such as an earthquake. This title usually includes police officers, firefighters, or EMTs. As a first responder, your primary responsibilities are to quickly and competently assess a situation and determine what other EMTs, police officers, or firefighters need to know when they arrive. You provide initial rescue or first aid care, but unless you are an EMT, you save more advanced medical care for when the ambulance arrives. In other words, a firefighter may provide CPR to an accident victim, but they stop when the more qualified first responder can take over.