Abstract.A communication scheme based on the synchronization of two chaotic semiconductor lasers is experimentally tested. The Chaos in the single-mode semiconductor lasers is generated by means of an optoelectronic feedback. Synchronization of the chaos is achieved by coupling a fraction of the transmitter's output power into the driving current of the receiver. We present experimental results on the route to chaos and the synchronization of GHz chaotic signals. We then test a proposed communication scheme by successfully transmitting messages.