Abstract: A gripper for a catheter shaft is a flexible tube surrounding a portion of the catheter shaft. A physician can move the gripper to a selected position on the catheter shaft, and then squeeze the outer surfaces of the gripper, which resiliently collapses around the catheter shaft. When squeezed, an inner surface of the gripper contacts the catheter shaft and can transmit forces applied by the physician to the outside of the gripper, including twisting of the catheter shaft or longitudinal pushing or pulling. The physician may then release the squeezing pressure, and has the option to move the gripper along the catheter shaft to a different position, and may choose to use the gripper at the new position by squeezing it again.