This book describes the design and implementation of the software for the control office for a GPS based Vehicle Tracking system. The design of a GPS based Vehicle Tracking system is based on three different modules namely GPS (Global Positioning System) modules for capturing the position information, microcontroller module for coordinating the three modules and GSM (Global System for Mobile communications) module for transmitting the information in the form of sms. The data captured by the GPS receiver is in RMC format of NMEA standard which not only gives the Latitude and Longitude but also the time , date, number of active satellite used, speed over ground, and track angle. The software interface is used at the receiving end (control office) to show the position of the vehicle on a map. Wikimapia.org and atlas.mapquest.com is used for this purpose.