Lieutenant General Ray Odierno knows Iraq well.
Gen Odierno was behind the plan that is credited with reducing violence
Before President George W Bush appointed him to be the top US commander in the country, General Odierno had served as the deputy to General David Petraeus, who has been promoted to take charge of US Central Command.
After Gen Odierno's appointment was approved by the US Senate in July, some analysts put the promotion down to his involvement with the successful US "surge" strategy in Iraq.
He was a driving force behind the 2006 troop-increase plan that put a rampant insurgency on the back foot and drove down levels of violence across the country.
The US Defence Secretary, Robert Gates, has said the general has the right qualities to command US forces in Iraq.
"Gen Odierno is known recently to the Iraqi leadership," said Mr Gates. "He's known to the Iraqi generals, and he is known to our own people."
"He has current experience and so the likelihood of him being able to pick up - for this baton-passing to be smooth - is better, and the odds are better with him than with anybody else I could identify."
The "baton-passing" comment is telling, and analysts say the decision by the Bush administration to replace Gen Petraeus with his right-hand man in Baghdad suggests Washington sees continuity as the best strategy in Iraq.
Gen Odierno's mindset reflects that of his former boss in Iraq.
As well as the troop surge, Gen Odierno echoed Gen Petraeus's concerns about Iran, saying the Islamic Republic was the most serious long-term threat to Iraq.
"If you ask me what I worry about most, I do worry about that (Iran supporting insurgents in Iraq) as a long-term threat," he has said.
"And I think we have to, you know, constantly watch it."
Back to Iraq
The towering shaven-headed general made his first tour of duty in Iraq in 2003 as commander of the Army's 4th Infantry Division.
The unit was based in Saddam Hussein's hometown of Tikrit, and the area was home to the country's nascent insurgency. Gen Odierno gained a reputation for his policy of tough tactics.
Although his unit was acclaimed for the eventual capture of Saddam Hussein, it was also criticised by some analysts for its heavy-handed approach. Some argued that rather than quelling the insurgency, the unit was driving local people into its arms.
Gen Odierno left Iraq in 2004, but returned in 2006 with a different strategy.
In a recent report in the Washington Post, retired Army Col Stuart A Herrington - who wrote a 2003 report for the military that identified Odierno's unit as "the major offender" in carrying out indiscriminate detentions of civilians - said Gen Odierno had "experienced an awakening".
Gen Odierno is held in high esteem both in Washington and Baghdad
"I've now completely revised my impression of him," he was quoted as saying. "He recognised that his guys were very, very heavy-handed before and realized tactics had to change."
A New Jersey native and science graduate of the esteemed US Military Academy at West Point, he later studied Nuclear Effects Engineering and National Security and Strategy at North Carolina State University and the Naval War College.
Having served as a platoon leader in Germany, he completed his officer training and was posted to Fort Bragg, North Carolina before returning to the Middle East for Operation Desert Storm in 1991.
After various senior roles in Europe and the Pentagon, Gen Odierno was assigned to Fort Hood, Texas as the commanding general from 2001 to 2004 of the 4th Infantry Division.
In 2004, he was promoted to be assistant to the chairman of the joint chiefs of staff in the Pentagon, as well as Secretary of State Condoleezza Rice's senior military advisor, accompanying her on state visits.
Returning to Iraq for his second deployment in May 2006, Gen Odierno assumed the mantle of commanding general of the multi-national corps in Baghdad.
A decorated soldier, Gen Odierno has been awarded the Army Distinguished Service Medal, the Legion of Merit with five oak leaf clusters, and the Meritorious Service Medal with three oak leaf clusters, among other decorations.