How do seismic waves travel through rock? How can satellites help with earthquake prediction? The 'Why Science Matters' series demonstrates how the science we learn at school is important in every aspect of our everyday lives. Using case studies and investigations, the series describes the development of science and technologies that can improve our lives - or lead to new scientific challenges and controversies. In 'Predicting Earthquakes', we learn about the structure of Earth and how earthquakes happen. We find out about faults and epicentres, the science behind seismographs, and the role of earthquakes in causing tsunamis. We also find out about the challenging tasks of anticipating movements in Earth's crust.