Abstract: A device and system for monitoring speed limit violations of a driver is disclosed. The monitoring device according to the invention is installed in the vehicle and programmed to provide an alarm whenever a programmed speed limit has been exceeded. According to the disclosed system, legal speed limit, and other appropriate traffic signs are provided with transmitters which broadcast an encoded speed limit signal. The monitoring device is provided with a receiver which is capable of receiving the transmitted signal. Upon receiving the transmission, the monitoring device updates the programmed speed limit. The transmitted signal includes a system identification string to enable the monitoring device to validate the signal. In addition, the monitoring device validates the encoded speed limit. In the preferred embodiment a library of digitized voice messages provides warning appropriate to the driving condition and driving speed.