He was a foreign policy adviser to the President from 2000 to 2006.
He will become a special policy adviser in its Washington office.
"I'm not coming in just to be the foreign policy adviser of the president," he said.
So what exactly does a domestic policy adviser do for a former president?
His economic policy adviser says the best way to meet the economy's current needs is to improve the education and training of those already here.
During the 1992 presidential campaign, he was one of Clinton's chief foreign policy advisers.
But she was a successful attorney and policy adviser before her husband became President, so why not after?
In 2005, Clinton appointed him as her senior defense and foreign policy adviser.
A policy adviser has been quietly taking notes at each stop.
"There's a lot up in the air," one senior foreign policy adviser said.