Identifying vulnerable groups and ensuring that their needs are met during disasters--whether naturally occurring or manmade--are vital aspects of preparedness planning. Developing preparedness strategies that are responsive to those at greatest risk is a moral mandate, justified by the principles of beneficence, justice, and respect for autonomy. Individuals with preexisting mental disorders and newly emergent psychological symptoms are particularly vulnerable to adverse outcomes during and after disasters. Without advance planning, these individuals might not benefit from necessary mental health services and treatments during and after disasters. In this commentary, we discuss ethical issues that arise in emergency preparedness planning for vulnerable individuals with psychological and psychiatric conditions and disorders.