What is the proper Army use/wear of the NATO Meritorious Service Medal?

Check AR 600-8-22 pg 126.
9–12. North Atlantic Treaty Organization Meritorious Service Medal
a. The NATO MSM is awarded to military and civilian personnel who have been commended for providing
exceptional or remarkable service to NATO.
b. The eligibility criteria for award of the NATO MSM includes: military and civilian personnel must not have been
convicted of serious misconduct or crimes during the period of assignment under NATO command and control; must
be serving permanently or temporarily within NATO’s operational chain of command or in those forces under NATO
command or control or in a NATO body; must be commended personally by a commander or a head of a NATO body
for one of the following:
(1) Performing acts of courage in difficult or dangerous circumstances.
(2) Showing exceptional leadership or personal example.
(3) Making an outstanding individual contribution in any activity or program.
(4) Enduring particular hardship or deprivation in the interest of NATO.
c. A period of qualifying service is not required. There is no limit to the number of times an individual may be
recommended for the NATO MSM.
d. Where individuals by nature of their duties or location qualify for an operational award, such individuals may
also be considered for the award of the NATO MSM in accordance with the criteria detailed above.
e. Award of the NATO MSM to personnel killed, presumed killed, or repatriated, as a result of being wounded or
seriously injured while on assignment may be considered.
f. Order of precedence. The NATO MSM will be worn in the order of their receipt after all U.S. decorations, the
Good Conduct Medal, campaign and service medals, and service and training ribbons.

The NATO Meritorious Service Medal is a decoration (ie. I did something) as opposed to a service medal (i.e. I was there). It would be worn before all other international and foreign awards but after the lowest award issued by the US Government (in your case probably the Overseas Service Ribbon). I understand that they award only about 150 of them a year and, I would guess, most of those are to officers and senior NCOs. Congratulations!

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