The theft of cars and other automobiles by criminals has become so frequent in our society as to be classified as alarming. Most of the thefts are organized by gangs of robbers but sometimes individuals engage in this activity. The result usually, however, is that the persons from whom the vehicles have been stolen are left to grieve as many of these vehicles are never recovered. This paper describes a simple alarm system that can be easily installed in all kinds of vehicles. The system described will effectively defeat intended car thieves.