Microearthquake (MEQ) activity recorded on a local network at The Geysers geothermal field has been observed to increase dramatically within seconds to minutes after the arrival of surface waves from large regional earthquakes. This behavior was observed not only following the 1992 Landers earthquake, for which remotely triggered seismicity (at The Geysers and elsewhere) has been documented, but also for the following events: Gulf of Alaska (MS 7.6, March 6, 1988); Loma Prieta (MS 7.1, October 17, 1989); two events within the Gorda Plate (MS 6.9 on July 13, 1991 and MS 7.1 on August 17, 1991); Petrolia (MS 7.0, April 25, 1992); and Northridge (MS 6.6, January 17, 1994). The exact onset times of most swarms are difficult to pinpoint, but all start within minutes of the passage of seismic waves and in at least one case (Gulf of Alaska) the onset appears to coincide with the expected arrival of the surface waves. These swarms generally last for a few hours at most, and decay with time in a manner similar to aftershock sequences. We propose that the dynamic stresses associated with seismic waves emanating from these earthquakes may trigger the onset of these swarms. The Landers event may have been particularly efficient at generating remotely triggered swarms throughout the western U.S. because of its size and shallow focal depth, which would promote large surface waves. Our data demonstrate, however, that the phenomenon is not unique to the Landers event. ¿ American Geophysical Union 1996