Emily Hammond is Associate Dean for Public Engagement and a Professor of Law at George Washington University Law School. Her article discusses the 2011 Fukushima nuclear disaster, which presented a familiar scenario from a risk perception standpoint. It combined a classic “dread risk” (radioactivity), a punctuating event (the disaster itself), and resultant stigmatization (involving worldwide repercussions for nuclear power). Some nuclear nations curtailed nuclear power generation, and decades-old opposition to nuclear power found a renaissance. In these circumstances, risk theory predicts a regulatory knee-jerk response, potentially resulting in inefficient overregulation. But it also suggests procedural palliatives that conveniently overlap with administrative law values, making room for the engagement of the full spectrum of stakeholders. This Article sketches the U.S. regulatory response to Fukushima. From a positive perspective, this story provides a useful case study for understanding administrative agencies’ responses to disasters and the concomitant role of risk perception. But this story also invites using an administrative law lens to take a fresh look at the issues of retroactivity and stakeholder engagement. This Article concludes by identifying insights as well as research needs for both regulatory responses to disaster and classic administrative law.