Abstract: For a child or adult sitting in a car seat, a head protector having a cushion body with a cushion back portion and opposite cushion side portions together defining a recess that is open at the front and bottom of the cushion body, with a front opening into the recess that is large enough to pass the child's or adult's head and a bottom opening for passing the child's or adult's neck, and channel-shaped mounting members behind the cushion body for snug but slidable insertion over the top of the seat back of the car seat.