General Joseph F. Dunford, Jr., speaks to the attendees of the change of command ceremony Friday at Marine Corps Barracks Washington, D.C. After more than 44 years of military service, Gen. James F. Amos, the 35th commandant of the Marine Corps passed the duties as senior-ranking officer of the Marine Corps to Dunford. (Photo by Cpl. Clayton J. Filipowicz/ Marine Corps)

Gen. Joseph Dunford, who led coalition military forces in Afghanistan for most of the last two years, took over as the new top officer in the Marine Corps on Friday, replacing retiring Gen. James F. Amos in a ceremony on the lush green lawn at Marine Barracks Washington.

Dunford, 59, will lead the service as it continues to shift focus after more than a decade of war in Iraq and Afghanistan. The Marine Corps is shrinking from a peak of about 202,000 service members at the height of the Afghanistan war in 2010 to no more than 182,100, and has launched a number of new, land-based crisis-response units to respond to emergencies that threaten Americans and U.S. interests abroad.

Dunford said Friday that he is humbled to be the 36th commandant, and credited Amos and his wife, Bonnie, with strong leadership.

“My focus in the coming years will be to take care of our Marines and their families, and to ensure  our Corps remains an expeditionary force of readiness our nation has come to expect,” he said.

In a letter to all Marines, he added that he engage with Marines of all ranks, developing “detailed Commandant’s Planning Guidance in the New Year.”

Dunford’s selection as the new top Marine was announced in June. He had been seen by many as the presumptive frontrunner for the position. He served as the Marine Corps’ assistant commandant — its No. 2 officer — from October 2010 until December 2012, when he stepped down ahead of becoming the top U.S. general in Afghanistan.

Dunford, an infantry officer, is seen as one of the Marine Corps’ brightest leaders, and as an even hand who won’t ruffle easily as his service adjusts to life after two long wars. He earned his nickname, “Fighting Joe,” while leading Marines in Iraq during the U.S. invasion there in 2003.

Amos, 67, led the Marine Corps from October 2010, and was the first aviator to lead the service — a point of contention for some, considering its focus on the infantry. A career fighter pilot, he oversaw the service through a tumultuous period marked by heavy combat and sacrifice by Marines in southern Afghanistan, budget cuts and the introduction of new high-tech equipment like the F-35B Joint Strike Fighter.

Amos has been dogged by tough criticism for several years, however. Notably, a whistleblower complaint was filed against him in March 2013 alleging that he and other members of his staff unlawfully inserted themselves into legal cases to ensure harsh punishment for Marine snipers who urinated on dead Taliban insurgents in Afghanistan and recorded video of their actions. The Defense Department Inspector General recently cleared Amos of wrongdoing, but the case remains deeply controversial in the service.

More recently, Amos has been accused of padding his resume to say that he completed officer training in person in 1972, something he acknowledged before Congress ahead of his confirmation as commandant. He actually completed the course through written correspondence, Marine officials confirmed last week.

This post has been updated with additional reporting.