GEOSEA XII in Bangkok, 7-8 March 2012 was organized by the Geological Society of Thailand (GST) in cooperation with Ikatan Ahli Geologi Indonesia (IAGI), Myanmar Geosciences Society, Geological Society of Malaysia, Geological Society of the Philippines and various national geoscience organisations. The theme of the event “Geoscience in Response to the Changing Earth” was selected to address geoscientific and strategic issues of common interest in the region and the world, especially the mega geological hazards, which are one of the greatest threats our planet is facing.