A tracking and positioning system and method to enable the precise positioning of an object or tool relative to its surgical surroundings, and in accordance with preoperative CT images of the operating site. When used for artificial spinal disc positioning, the system comprises a computing system incorporating in memory the preoperative CT data showing the two vertebrae and the predetermined disc position between them; a 3-D target having radio-opaque markers for attaching to one of the vertebrae to define the position of the vertebra in an intra-operative fluoroscope image of the spine; a tool for intra-operative insertion of the artificial disc, and a registration system for relating the intra-operative fluoroscope image to the preoperative CT data, such that the predetermined disc position is displayed in the fluoroscope image of the subject, thereby enabling the surgeon to place the artificial disc accurately in its intended position.