Abstract: A surgical site monitoring system and associated method of use employ a single scan-visible passive vectorized fiducial reference attached at a fiducial location near a surgical site. A passive vectorized tracking marker is attached to the fiducial reference. Passive vectorized tracking markers may also be attached to surgical implements used at the surgical site. A scan prior to a surgical procedure with the fiducial reference attached is used to obtain scan data of the surgical site. A tracker obtains image information about the tracking markers and surgical implements. The system and method employ the scan data and image information to track the surgery and the surgical implements relative to the surgical site. The system and method use either markings on or shapes of the tracking markers to determine from the image information the relative 3D locations and orientations of the surgical implements and fiducial reference.