On March 11, 2011 eastern Japan was struck by a magnitude 9.0 earthquake and an enormous tsunami, over 13 m in height, which together killed over 20,500 people and resulted in the evacuation of over 320,000 people from the devastated areas. This paper describes the damage sustained by the Fukushima-Daiichi nuclear power plant during this unpredicted major natural disaster and the events that happened in the months after this accident. The events occurring at the Fukushima-Daiichi nuclear power plant, the actions taken to minimize the effects of the damage to the plant and to protect the public, and the points at which the responses proved to be inadequate all offer lessons that will be of value to those planning for and responding to future natural disasters and accidents in Japan and around the world.