The international fusion experiment ITER may get a new director-general after suffering delays and cost overruns. Osamu Motojima, a distinguished Japanese physicist, is being floated as the project's new chief, Nature has learned. The appointment, if made, may trigger further changes for the project. "I wouldn't be surprised if there's a huge shake-up in ITER management under him," said one fusion scientist familiar with the project.

Motojima would replace Kaname Ikeda, who has led the programme since its inception in 2007. Ikeda was originally appointed for a five-year term, and his departure would be the second high-level management change in recent months. In February, Europe's project head, Didier Gambier, was replaced by British physicist Frank Briscoe (see Nature 463, 721; 2010).

ITER spokesman Neil Calder said that the organization would consider management changes at the next council meeting in June. However, he would not confirm whether Motojima is a candidate for the directorship.

Researchers hope that ITER, based in the south of France, will prove the viability of nuclear fusion as a power source. The doughnut-shaped reactor will heat and squeeze hydrogen isotopes until they fuse together, forming helium. The process is expected to release ten times the power it consumes. ITER's seven members — Europe, Japan, the United States, South Korea, China, Russia and India — hoped to build the project by 2016 at a cost of €5 billion (US$6.3 billion). But that cost is expected to double, and first experiments are now set for late 2019. On 5 May, the European Commission announced that it faces a €1.4-billion funding gap for construction between 2012 and 2013.

Motojima has a long career in fusion research. From 1999 to 2002, he oversaw construction of a fusion machine called the Large Helical Device (LHD) at the National Institute for Fusion Science in Toki City, Japan. The LHD uses a twisted loop of magnets to wrangle hot gas, a more complex set-up than the doughnut-shaped ITER device. Despite this, Motojima saw the LHD completed on schedule, says Hutch Nielson of Princeton Plasma Physics Laboratory in New Jersey. "I think Motojima's record there was a complete success," he says.

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NATIONAL INSTITUTE FOR FUSION SCIENCE