A child seat attachment system for a vehicle seat having a seat cushion and a seat back extending upwardly from the rear end of the seat cushion. The child seat attachment system includes a cross-bar extending laterally of the seat where at least one end of the cross-bar can be coupled to the mounting mechanism for attaching either or both of the seat cushion and seat back to the vehicle. The cross-bar has a child safety seat anchorage portion projecting through the bight line of the seat between the seat cushion and seat back for attachment of the child safety seat thereto. In a preferred embodiment, the cross-bar is rotatable about a lateral axis to enable the cross-bar to move downward against the seat cushion when the seat is occupied by an adult seat occupant to improve the comfort for the adult seat occupant.