Kōji Yamazaki

He also served as the Director of the Logistics Management Division, as commander of the 8th Facility Battalion while subsequently serving as the Facility Manager of the 8th Division (Japan) headquarters and as the Sendai garrison commander under the North Eastern Army in March 2001.

Yamazaki was also the commanding General of the 4th Engineer Brigade, based in Camp Okubo in Uji, Kyoto Prefecture in 2008.

In August 2017, he was appointed 35th Chief of the Ground Staff of the Japan Ground Self-Defense Force, the highest position in the JGSDF after the resignation of General Toshiya Okabe and former Defense Minister Tomomi Inada amidst claims over a cover up scandal within the Ministry of Defense, exposing the danger Japanese peacekeepers were facing in South Sudan.

[12] However, his extensions was cut short and he retired from the service on 30 March 2023, where he was replaced by General Yoshihide Yoshida.

[13] On 12 July 2023, Yamazaki was appointed to serve as an advisor to the Ministry of Defense, where he replaced Kazuhisa Shimada.

Then-Vice Chief of Staff Lt. Gen. Koji Yamazaki (right), with Maj. Gen. Takuto Ogasawara (left), Joint Staff College Ministry of Defense Vice Commandant, and Lt. Gen. John L. Doland (middle) of United States Forces Japan during the Japan Joint Staff 10th anniversary ceremony at Hotel Grand Hill, Ichigaya, Japan
Chief of Staff Koji Yamazaki shakes hands with Lt. Gen. Lawrence D. Nicholson of the III Marine Expeditionary Force (2017)
Gen. Koji Yamazaki, with US Chairman of the Joint Chiefs of Staff Gen. Mark A. Milley and South Korean Chairman of the Joint Chiefs of Staff Gen. Park Han-ki at a multilateral meeting at Washington, D.C.
General Yamazaki with Lieutenant General Aviv Kochavi during his visit in Israel (2019)
General Yamazaki (2nd from left) meets with US Admirals John C. Aquilino and Philip S. Davidson , US Chairman of the Joint Chiefs of Staff Gen. Mark A. Milley , and South Korean Chairman of the Joint Chiefs of Staff Gen. Won In-choul (2021).