Disasters continue to increase in frequency and affect more and more citizens of the world community. Economic costs are increasing at an alarming rate. The death toll in the last 50 years has been in excess of 12 million persons, billions of people have been “affected”, and economic costs are estimated as high as US$4 trillion. Human and economic costs have been estimated for disasters caused by natural and manmade events. Manmade events are segregated into technological and inter-human conflicts. Defined human costs do not include those effects such as short- and long-term psychosocial problems that cannot be quantified. The lack of structure for the conduct of research and evaluation of interventions impairs our ability to learn from experiences. This Chapter introduces a structural framework for investigations into the medical and public health aspects of disasters including: (1) a standardized, universal set of definitions; (2) a conceptual model for disasters; (3) indicators and standards; (4) descriptions of 14 basic societal functions bound together by a coordination and control function; and (5) a disaster response template and two research templates. The templates are to be used in the design, conduct, analysis, and reporting of research and/or evaluations of interventions directed at preventing hazards from becoming a disaster-producing event, mitigating the effects of such an event on the affected society, and/or responses to a disaster.