Abstract: An apparatus and method for guiding a surgical instrument within and around the human body. The invention employs a light emitter and an array of light sensors and a display to accurately locate an anatomical feature into which the light emitter has been placed. Laser or LED light emitted from an emitter, conveyed by a light conduit, is detected after passing through a thickness of bone and/or soft tissue by the sensor array. The signal from the sensor array is processed-and information indicating the relative direction of the emitter from the sensor is displayed. The light can be directed by a mirror or by bending the end of the light conduit.