This document summarizes a vehicle theft detection and tracking system that uses GPS and GSM technologies. The system constantly monitors the location of a vehicle using GPS and reports the status to an authorized user via GSM upon request. If a theft is detected, the user can send an SMS message to the microcontroller to stop the engine. To restart the vehicle, the authorized user must send a password to the microcontroller via SMS. The system provides vehicle tracking, theft prevention and retrieval at a low cost.