As secretary of state, Clinton will become the face of American diplomacy around the world, representing the man who beat her for the Democratic nomination.
Just two days ago, sources told ABC News that Clinton said she was inclined to reject the offer and resume her career as a United States senator. However, Obama's transition team encouraged her to wait and think it over, and then Thursday night according to the New York Times, she accepted.
"It's a very bold move. It's a healing move for the Democratic Party and it brings in somebody who is very experienced and knowledgeable," said ABC7 political analyst Bruce Cain.
Cain says that for Clinton it was a choice between returning to the Senate where she still lacks seniority or accepting the high profile Cabinet position.
"At her age, to wait a decade to get a committee chair, that's just too long. That's not something she wants to do," said Cain. "I think she is realizing that her chances to make policy might be greater with Obama."
Cain says Clinton brings a lot to the table.
"She also has international experience. She has traveled widely. She has her husband as a resource," said Cain.
As secretary of state, Clinton would be in a position to help repair strained relations with other countries and to steer U.S. foreign policy But in so doing, she will also have to put Obama's agenda ahead of her own, which could be tough for a former White House resident.
"She's going to actually want to be, if not driving the car, riding shotgun so she can help get the credit and lay her fingerprints all over whatever comes out," said Erin Billings of Roll Call.
Clinton's decision follows days of intense negotiations intended to clear any conflicts of interest due to her husband's global business and charitable activities. Details are still being worked out, but Obama is expected to announce her nomination after Thanksgiving along with other members of his national security team.