This chapter begins by stating that the need for and value of preparation for extraordinary events are axiomatic in the disaster mental health field. It assumes a healthcare system that is, at minimum, composed of public health, hospital and community medical services, emergency medical services and specialty health and medical care. Although the field of disaster mental health is relatively young, overall planning has evolved significantly over a long period of time. The National Response Plan (NRP) forms the basis of how the federal government coordinates with state, local, and tribal governments and the private sector during incidents. There are many useful sources of information and guidance for healthcare system disaster planning found throughout the chapter. Overall relationships in the disaster response environment should be guided and informed by the requirements of the NRP. The chapter concludes with describing implications for public health, clinical care, and research.