An auxiliary rotary tool drive apparatus mounted on, or an integral component of, hand-held rotary power tool has an extendable and retractable auxiliary drive shaft and a gear assembly that is selectively operatively engaged with the power transmitting shaft and gear assembly of the power tool and driven thereby using only the hand grasping the power tool for driving screws, fasteners, bits or other work performing members attached to the auxiliary drive shaft without having to move or remove the existing work performing member from the holding member of the power tool.