For heroic achievement in connection with combat operations against the enemy in the Republic of Vietnam while serving as Motor Transport Chief of Battery E, Second Battalion, Eleventh Marines, First Marine Division. Early on the morning of 19 August 1969, the Battery E position at the An Hoa Combat Base was attacked by a North Vietnamese Army Sapper unit employing automatic weapons, rocket-propelled grenades, and various explosive devices. Reacting instantly, Corporal Chiles manned his station near the command post and coordinated communications between isolated sectors of the perimeter. Upon learning that the enemy had overrun a friendly position, he boldly advanced across the fire-swept terrain toward the position. As he advanced, he discovered that one gun position had been captured by the enemy. Without hesitation he attacked the enemy-held gun position and, firing his rifle, assisted in routing the enemy from the gun pit. Observing a wounded Marine lying in an area dangerously exposed to hostile fire, Corporal Chiles maneuvered forward, administered first aid to the casualty, and then carried him back to a relatively secure area. Throughout the fire fight, he repeatedly disregarded his own safety to gain vantage points from which to direct fire against the enemy. When the enemy fire subsided, Corporal Chiles assisted in a search of the area to ensure that all of the enemy sappers had been routed. His heroic actions inspired all who observed him and were instrumental in thwarting the enemy's attempt to overrun the friendly position. Corporal Chiles's courage, bold initiative, and unwavering devotion to duty at great personal risk were in keeping with the highest traditions of the Marine Corps and of the United States Naval Service