Ellwood says Shalala's personality--which Shalala describes as "enthusiastic"--made her a perfect fit for the job.
"She is caring and thoughtful, but she can be tough when she needs to be, which makes for a terrific combination," he says.
Despite her longevity as HHS, Shalala says that once the Clinton administration ends, she will not serve in another Cabinet or run for any public office and will most likely return to a university setting.
She says she "might" consider teaching at Harvard after HHS.
"My career has been characterized by larger and larger responsibilities and more interesting jobs," Shalala told The Times. "It's harder to get bigger and more interesting than this."