A surgical navigation system, comprising: an imaging system operable to acquire image data; a first tracking device associated with the imaging system, the imaging system including, a rail system surrounding a central axis; a rotor operable to move on the rail system around the central axis; an emission portion and an imaging portion mounted on the rotor 180° from one another and operable to move with the rotor around the central axis; an annular gantry housing surrounding the rail, the rotor, the imaging portion, and the emission portion and also surrounding the central axis; and a mobile cart mounted to the gantry housing; a second tracking device and a third tracking device associated with a subject operable to be imaged with the imaging system; a first tracking system operable in a first manner to track at least the first tracking device and the second tracking device in a first navigation space, including a first localizer; and a first tracking determining portion; a second tracking system operable in a second manner to track the third tracking device in a second navigation space, including a second localizer; and a second tracking determining portion; and a navigation system operable to execute instructions to determine a location of the first tracking device, the second tracking device, the third tracking device, or all of the first tracking device, the second tracking device, and the third tracking device in the first and second navigation spaces and wherein the gantry housing is operable to be positioned relative to the mobile cart in at least one of the vertical position, a horizontal position and a rotational position, said surgical navigation system being characterized in that the navigation system is operable to correlate the first navigation space of the first tracking system and the second navigation space of the second tracking system by the tracking of the second tracking device with the first tracking system and tracking the third tracking device with the second tracking system to determine the location of a reference point in both the first and second navigation spaces; and in that the first tracking device is mounted on the gantry housing. an imaging system operable to acquire image data; a first tracking device associated with the imaging system, the imaging system including, a rail system surrounding a central axis; a rotor operable to move on the rail system around the central axis; an emission portion and an imaging portion mounted on the rotor 180° from one another and operable to move with the rotor around the central axis; an annular gantry housing surrounding the rail, the rotor, the imaging portion, and the emission portion and also surrounding the central axis; and a mobile cart mounted to the gantry housing; a rail system surrounding a central axis; a rotor operable to move on the rail system around the central axis; an emission portion and an imaging portion mounted on the rotor 180° from one another and operable to move with the rotor around the central axis; an annular gantry housing surrounding the rail, the rotor, the imaging portion, and the emission portion and also surrounding the central axis; and a mobile cart mounted to the gantry housing; a second tracking device and a third tracking device associated with a subject operable to be imaged with the imaging system; a first tracking system operable in a first manner to track at least the first tracking device and the second tracking device in a first navigation space, including a first localizer; and a first tracking determining portion; a first localizer; and a first tracking determining portion; a second tracking system operable in a second manner to track the third tracking device in a second navigation space, including a second localizer; and a second tracking determining portion; and a second localizer; and a second tracking determining portion; and a navigation system operable to execute instructions to determine a location of the first tracking device, the second tracking device, the third tracking device, or all of the first tracking device, the second tracking device, and the third tracking device in the first and second navigation spaces and wherein the gantry housing is operable to be positioned relative to the mobile cart in at least one of the vertical position, a horizontal position and a rotational position, said surgical navigation system being characterized in that the navigation system is operable to correlate the first navigation space of the first tracking system and the second navigation space of the second tracking system by the tracking of the second tracking device with the first tracking system and tracking the third tracking device with the second tracking system to determine the location of a reference point in both the first and second navigation spaces; and in that the first tracking device is mounted on the gantry housing.