This comprehensive analysis addresses the United States' alarming lack of preparedness to respond effectively to a massive disaster as evidenced by Hurricane Katrina. First, a timeline of problematic response events during and after Hurricane Katrina orients readers to some of the specific problems encountered at different levels of government. Second, a list of the "Dirty Dozen"--12 major failures that have occurred in prior disasters, which also contributed to inadequate response during and after Hurricane Katrina--is presented. Third, this article encourages expanding psychology's role beyond the treatment of trauma to encompass disaster planning and mitigation efforts from a broader public health perspective. Finally, areas for important interdisciplinary research in human behavior that will influence our nation's overall preparedness for future catastrophes are identified, and ways psychologists can become personally involved beyond treating casualties are discussed.