The present invention relates to a medical tracking system comprising at least one sensor device which can be positioned in a fixed position relative to a target, the sensor device comprising a marker device and a marker device detector, the marker device detector being capable of obtaining information for determining a relative position between the marker device detector and another marker device, the system further comprising a control unit configured to process a medical navigation workflow and to select the function of the sensor device as either acting as a marker device detector or as a marker device in a step of the medical navigation workflow.