Throughout the Vietnam War, the Military Merit Medal was awarded solely to enlisted U.S. service members who had been killed in action, while the National Order and Distinguished Service Order were awarded only to senior U.S. military personnel. By far the most common Vietnamese decorations awarded to U.S. troops were the Vietnam Campaign Medal and the Gallantry Cross Unit Citation; the Campaign Medal was awarded for six months of service in Vietnam while the Gallantry Cross unit citation was almost automatic for U.S. Army personnel and quite common in other service branches as well. In 1974, a General Order of the U.S. Army made the Gallantry Cross Unit Citation automatic for any soldier who had spent any amount of time in Vietnam; this has led to this decoration being arguably the most commonly awarded foreign decoration of all time.
The Civil Actions Medal and unit citation were also commonly awarded to members of the United States Marine Corps making this a very common decoration seen on U.S. Marine Corps uniforms. The remainder of Vietnamese medals, such as the Air and Navy Gallantry Cross and the Staff and Special Service Medals, were awarded with different frequency between the U.S. service branches and amongst officer/enlisted personnel.
In the 21st century United States military, the Vietnam Campaign Medal, the Gallantry Cross, and the Gallantry Cross/Civil Action/Presidential unit citations are still authorized for wear on U.S. uniforms and many senior officers today, who began their careers in Vietnam, can be seen wearing such medals. However, since the nation of South Vietnam no longer exists, these medals and ribbons must be privately purchased and there are no channels for the retroactive award of said medals, except in the case of the Vietnam Campaign Medal and the Gallantry Cross Unit Citation which are considered automatic decorations and can be added to a DD Form 214 by request through the military service branch or through NPRC in St. Louis, Missouri.