Atkinson succeeds Michael Froman, who was sworn in as the U.S. Trade Representative, the White House said in a release Friday.
Atkinson has been special assistant to the president for international economic affairs since August 2011.
In her new role, she will be President Barack Obama's personal representative to major international economic summits, and serve as his senior international economic adviser.
"Caroline is respected around the world for her understanding of how the global economy works, her tireless efforts to promote strong, balanced and sustainable growth and her experience in managing international financial crises," Obama said in a statement.
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