Abstract: The seat adjustment and inertial locking mechanism is suitable for use with walk-over seats, as well as with other vehicular seats that have a movable seat back. The inertial locking mechanism includes a first rotatable cam member that engages a linearly-movable first locking member when the vehicle is traveling in a first direction and undergoes rapid deceleration. A braking surface on the first cam member engages a braking surface on the locking member to prevent further movement of the seat back. In a walk-over seat when the seat back has been moved to the second position and when the vehicle is traveling in a second direction, the second rotatable cam member engages a linearly-movable second locking member upon rapid deceleration of the vehicle. An adjustment means is also provided for tilting the bottom seat cushion when the seat back is moved from the first position to the second position.