Systematic cataloguing of seismic moment, depth, and mechanism of regional earthquakes down to magnitude M~4 can now be achieved in close to real-time using data from sparse networks of digital broadband stations. The procedure we have developed relies on 3 independent methods for the determination of moment tensor, providing confidence limits on the results. We show the results of application to the seismicity in central and northern California for a one year period starting in March 1992 and illustrate how patterns of stress and strain release can now be monitored systematically and reliably in a timely fashion. ¿ American Geophysical Union 1993