Abstract: An improved combined torque limiting and part marking wrench according to the present invention includes: a torque-applying handle; a housing pivotally mounted to the handle, the housing adapted to receive a releasably mounted, replaceable, part-engaging head assembly at a second end thereof; and a part-marking mechanism mounted within the housing. The part-marking mechanism includes a marking tip which passes through a bore in the head assembly for marking a part. A mechanical linkage arm is pivotally connected to the torque-applying handle. A pivotable cam is pivotally connected to the linkage arm and in operative engagement with the part-marking mechanism for moving the marking tip through the bore, such that, when torque on a part has reached a predetermined value, the torque applying handle moves the linkage arm, which pivots the pivotable cam, thus forcing the pivotable cam against the part marking mechanism, which causes the marking tip to extend outwardly from the housing to mark the part.