[en] This white paper aims at proposing answers to some questions regarding the situation in Fukushima and the consequences of the accident, notably the situation regarding dismantling, the remaining radioactive substances, lessons learned, and other issues. Thus, a first article presents the radio-ecology discipline and describes how this technique allowed the control and reduction of radionuclide transfers in Fukushima (interview of an IRSN expert). A second article addresses the transport of radioactive substances, more particularly in France where nearly hundred significant events are noticed every year. Classification (in terms of hazard) and regulation (technical requirements and others related to radioactive products and to their transport) aspects are overviewed. The third article addresses the evolution of the dismantling of the Fukushima Daiichi nuclear plant (interview of an IRSN expert). The last article discusses the action plan implemented by France to improve the safety of its nuclear installations, with the installation of back-up Diesel units, the installation of ultimate water sources to cool reactors, and the construction of local crisis centres able to withstand extreme aggressions. Five articles are also proposed. They address the French challenge of management of nuclear wastes, the development of small nuclear reactors everywhere in the world, the necessary adaptation of nuclear plants to extreme air temperatures, the safety of French nuclear installations which is globally good but still to be improved, and the causes and consequences of the Fukushima accident.