A system comprising: an implantable medical device comprising a first tilt detector in a known orientation relative to at least a portion of the implantable medical device; an orientation device comprising a second tilt detector; and an indicator that provides information to a user based on signals from the first and second tilt detectors, wherein the information is indicative of a relative orientation between the orientation device and the portion of the implantable medical device; and characterized in that the first and second tilt detectors each comprise an accelerometer; and wherein the signals comprise a first signal from the first tilt detector indicative of an orientation of the first tilt detector and a second signal from the second tilt detector indicative of an orientation of the second tilt detector, and the information indicates whether the first signal substantially matches the second signal; said system further comprising a processor that determines the relative orientation between the orientation device and the portion of the implantable medical device based on the signals from the first and second tilt detectors; wherein the signals comprise a first signal from the first tilt detector and a second signal from the second tilt detector, and the processor determines an offset between the first signal and the second signal to determine the relative orientation between the orientation device and the portion of the implantable medical device; said system further comprising an external medical instrument coupled to the orientation device; and further comprising a processor that controls a positioning device that automatically positions an external medical instrument relative to the implantable medical device based on the signals from the first and second tilt detectors. an implantable medical device comprising a first tilt detector in a known orientation relative to at least a portion of the implantable medical device; an orientation device comprising a second tilt detector; and an indicator that provides information to a user based on signals from the first and second tilt detectors, wherein the information is indicative of a relative orientation between the orientation device and the portion of the implantable medical device; and characterized in that the first and second tilt detectors each comprise an accelerometer; and wherein the signals comprise a first signal from the first tilt detector indicative of an orientation of the first tilt detector and a second signal from the second tilt detector indicative of an orientation of the second tilt detector, and the information indicates whether the first signal substantially matches the second signal; said system further comprising a processor that determines the relative orientation between the orientation device and the portion of the implantable medical device based on the signals from the first and second tilt detectors; wherein the signals comprise a first signal from the first tilt detector and a second signal from the second tilt detector, and the processor determines an offset between the first signal and the second signal to determine the relative orientation between the orientation device and the portion of the implantable medical device; said system further comprising an external medical instrument coupled to the orientation device; and further comprising a processor that controls a positioning device that automatically positions an external medical instrument relative to the implantable medical device based on the signals from the first and second tilt detectors.