On December 26, 2004, countries in the Indian Ocean basin were struck by a tsunami generated by a large magnitude earthquake just south of the western tip of Sumatra. Observations made during a post-tsunami visit to coastal Thailand suggest that the value of the proposed emergency warning system (EWS) for the Indian Ocean would be greatly enhanced if it was augmented by an on-shore cyber-based warning and evacuation system. Such a system would greatly increase safety with minimal disruption to the normal activities involved in tourism and other coastal industries. An integrated, cyber-based system to inform and assist the tsunami detection, warning, and evacuation process would, in essence, expand time and shorten distances. This paper describes the elements of such a cyber-infrastructure system, how system triggers could be calibrated using decision principles from judgment theory, and how the system could be tested through simulations employing agentbased models.