This book is aimed at building a secured and reliable vehicle anti-theft system which will have the ability to ac-cess the vehicle subsystems from a remote location where there is GSM network. And also, the design method involves the interfacing of GSM/GPRS modem module with the vehicle ignition subsystem, and the test result shows that it per-forms some control actions on the vehicle subsystems from a mobile phone, having taken the advantage of the wide coverage area of some GSM networks. Hence the topic is "Remotely Controlled Vehicle Anti-theft System via GSM Network".