Rear-facing
Children should ride in a rear-facing seat from birth until at least age two and ideally until they reach the maximum height or weight allowed by the seat. Rear-facing seats distribute crash forces across the entire back rather than concentrating them on a child's neck and head.
Forward-facing with harness
After outgrowing the rear-facing seat, children should use a forward-facing seat with a five-point harness until they reach the maximum height or weight for the seat — usually around age four to seven.
Booster seat
After outgrowing the forward-facing seat, children should use a booster seat with the vehicle's lap-and-shoulder belt. A booster raises the child so the seat belt fits across the strong bones of the hips and shoulders rather than the soft tissue of the abdomen and neck.
Seat belt alone
A child is ready for the seat belt alone when they can sit with their back against the vehicle seat, knees bent comfortably over the edge, lap belt across the upper thighs, and shoulder belt across the center of the chest and shoulder. This usually happens between ages eight and twelve.