Provide the key to trying to reduce the impact of an earthquake.
Prediction
When forecasting earthquakes, its difficult to be accurate, even if seismic records and foreshocks are analysed. In 2009, six scientists were sentenced to 6 years in prison (but it was overturned) as they failed to predict the 6.9 earthquake in L'Aquila.
Animal behaviour - toads all disappeared before the L'Aquila earthquake.
Seismographs record foreshocks.
Radon gas counter - levels of dissolved radon gas in groundwater
Magnetometer - measures slight changes in the Earth's magnetic field.
Monitoring levels of water in wells, shows changes in level of the underground water table.
Protection
Building design.
The Transamerican Pyramid Building (see top) is earthquake proof. It swayed more than one foot in the 1989 earthquake, but wasn't damaged. It sits on several underground rollers which allow the building to rock gently in the event of an earthquake.
Wellington's (NZ) Central Police Station: The exterior walls have X-shaped bracing that enables the buildings to move as a rigid body. The building rests on 24 flexible piles, isolating it from the ground, and it has lead dampers to reduce shaking.
Preparation
Community preparedness.
Education, e.g. Japan has the Disaster Prevention Day every year on the 1st September. Also, Great Shake Out Drills on 15th October 2015, expanding across the world as an annual event. They focus on 'Drop, Cover and Hold On.'
The early warning system in Japan - warning from the P-waves of the S-waves to come.