Abstract: A re-settable vehicle seat belt pre-tensioner apparatus is disclosed having a first member engagable with a second member that is moveable relative to the first member, and re-settable in response to various sensed driving conditions to pretension the seat belt around the operator and return to a non pre-tensioned status when the driving conditions have passed. The apparatus may be operated by positioning the belt for use; determining whether the seat belt buckle is in use; locking the pre-tensioner and lowering the seat belt buckle below the seat occupation plane; determining whether a threshold vehicle seat belt pre-tension load has been met; raising the belt buckle to a design position, unlocking the retractor; determining whether a threat event is imminent and locking the retractor; lowering the vehicle seat buckle relative to the plane of occupation, determining whether a crash event is occurring, and if yes, deploying a pyrotechnic deployment to secure the occupant in the seat.