A torque-transmitting, locking instrument holder, includes a hollow body having a proximal end for receiving an instrument, a distal end for protrusion of the instrument, and a handle to be gripped by an operator. A device is provided for locking the handle to and unlocking the handle from the instrument at least partly disposed within the hollow body. A method for operating the instrument holder includes providing a hollow body having a proximal end for receiving an instrument, a distal end for protrusion of the instrument, and a handle to be gripped by an operator. The instrument is placed at least partly within the hollow body and the handle is locked to and unlocked from the instrument.