President Obama nominated White House counterterrorism official John Brennan to head the Central Intelligence Agency and former Nebraska senator Chuck Hagel as Defense Secretary.
Brennan, a 25-year CIA veteran, will replace David Petraeus, who resigned last year after acknowledging an extramarital affair.
"John Brennan's career of service and extraordinary record has prepared him to be an outstanding director of the CIA," said a White House statement. "Since 9/11, he has been on the front lines in the fight against al-Qaeda. Over the past four years, he has been involved in virtually all major national security issues and will be able to hit the ground running at CIA."
In going with Brennan, Obama passed over acting director -- and Petraeus deputy -- Michael Morell.
Obama considered Brennan for the CIA post after his 2008 election, but Brennan withdrew his name after critics questioned his connections to enhanced interrogation techniques used by the CIA during the George W. Bush administration.
Brennan denied involvement in waterboarding and other harsh interrogation methods, and has spoken out against them.
Obama has credited Brennan for his work on a variety of issues, from the 2011 raid that killed 9/11 mastermind Osama bin Laden to counterterrorism efforts in Somalia and Yemen to the challenges of the Arab Spring pro-democracy efforts.
The White House adviser has also been involved in the administration's increased use of unmanned drones for surveillance and attacks on suspected terrorists.
Brennan's years at the CIA included stints at deputy executive director, station chief in Saudi Arabia, and top presidential briefer. He has worked in both Republican and Democratic administrations.