In the aftermath of the tragic events in Japan of 11 March 2011, I ampleased UNEP has been able to contribute to the post-disaster effort. One year after the disaster, the environmental, economic and social costs are still unfolding. A number of communities who were uprooted from their coastal villages may never return to those areas. Some of the disaster debris which was washed into the sea may yet turn up in other countries. The final closure and decommissioning of the Daiichi reactors in Fukushima remains a challenge, as does the rehabilitation of the no-go zone around the reactor. The disaster and Japan’s response to it has been closely watched by the international community. The lessons from this disaster are expected to change the rules of the game in a number of areas, from early warning to improved safe operation of nuclear industries. This report focuses on the enormity of the post-disaster debris challenge and documents the response by the people of Japan and key learnings one year after the event.