For conspicuous gallantry and intrepidity at the risk of his life above and beyond the call of duty while serving as an artillery liaison operations chief with the 2d Battalion. In the early morning hours the 2d Battalion was occupying a defensive position which protected a bridge on the road leading from Con Thien to Cam Lo. Suddenly, the marines' position came under a heavy volume of mortar and artillery fire, followed by an aggressive enemy ground assault. In the ensuing engagement, the hostile forces penetrated the perimeter and brought a heavy concentration of small-arms, automatic-weapons, and rocket fire to bear on the battalion command post. Although his position in the fire support coordination center was dangerously exposed to enemy fire and he was wounded when an enemy hand grenade exploded near his position, Sgt. Foster resolutely continued to direct accurate mortar and artillery fire on the advancing North Vietnamese troops. As the attack continued, a hand grenade landed in the midst of Sgt. Foster and his five companions. Realizing the danger, he shouted a warning, threw his armored vest over the grenade, and unhesitatingly placed his body over the armored vest. When the grenade exploded, Sgt. Foster absorbed the entire blast with his body and was mortally wounded. His heroic actions undoubtedly saved his comrades from further injury or possible death. Sgt. Foster's courage, extraordinary heroism, and unfaltering devotion to duty reflected great credit upon himself and the Marine Corps and upheld the highest traditions of the U.S. Naval Service. He gallantly gave his life for his country.