Online tracking of speakers is an important task for applications in smart environments such as camera control, meeting annotation and speech separation. Challenges for an audio-only system are small-room reverberation, noise, the unknown number of speakers, and gaps occurring in natural speech. Combining models from neurobiology and cognitive psychology with many-channel signal processing and pattern recognition techniques, a hybrid method was developed. By employing online CASA processing to signals from a microphone array, the real-time capable method is able to track an arbitrary number of concurrent moving speakers in highly reverberant environments. The video demonstrates tracking two speakers in a reverberant conference room (T60=0.64s) with a circular microphone array showing the speakers as recorded by an omnicam in the centre of the array.