A tracking device and system for tracking medical supplies, in particular, medical trays and their components is disclosed. The tracking device utilizes GPRS/GSM technology to enable an individual to locate and monitor the movement of a medical tray at any given time and for any desired period of time. The tracking system utilizes geo-fences established within buildings to assist in determining the specific location of the medical trays within these buildings. The tracking devices can also be activated by motion sensors to alert the tracking system of a possible theft of the tray. The tracking system incorporates software which enables an individual to determine the location of medical trays, determine the contents of the trays and schedule the use of the medical trays by specific doctors and at specific locations. The tracking system also retains information regarding the doctors, the medical device manufacture representatives, the hospitals and sales of the medical devices.