Tsunamis are infrequent, but when they happen, they can be catastrophic causing death and destruction across ocean basins, as was seen by the 2004 Indian Ocean Tsunami that resulted in nearly 228,000 casualties across 14 countries. In response in 2005, new tsunami warning and mitigation systems were established in the Indian Ocean, Caribbean, and North-Atlantic and Mediterranean to be able to alert countries and their populations for dangerous tsunamis. The systems joined the Pacific, which was established in 1965 in response to the M9.5 Chile earthquake and tsunami.  All are organized under the framework of UNESCO's Intergovernmental Oceanographic Commission (IOC), coordinated through regional Intergovernmental Coordination Groups (ICG/CARIBE-EWS, ICG/IOTWMS, ICG/NEAMTWS, ICG/PTWS) and supported by regional Tsunami Information Centres (CTIC, IOTIC, NEAMTIC, ITIC).

To test the system, and validate new products and procedures, the IOC and ICGs have organized and conducted regular exercises since 2006 (Exercise Pacific Wave 2006 was the first IOC Wave exercise).  The exercises also provide opportunities for countries to test regional coordination, and to practice their national and local tsunami warning procedures.