Polar Seismology" has been developed since the International Geophysical Year (IGY 1957-1958) and contributed significantly to global seismology in particular through the big project of the International Polar Year (IPY 2007-2008). At present, in the first stage of the twenty-first century, "polar regions" play an important role to monitor and understand the drastic variations in the Earth's system as well as to advance the interdisciplinary studies of the interactions among multispheres within the system.