Marine Corps · MOS history

8431 Psychological Operations Noncommissioned Officer

The 2006 MOS revision changed MOS 8431, Psychological Operations Noncommissioned Officer, to MOS 0521, moving it from the 8000/9000 category into a regular occupational field. Personnel implementation was deferred rather than taking effect automatically with the manual.

Codes named in this history

Other history records

These source identifiers have archive pages. Their availability does not establish current service use or retirement.

Documented history

Psychological Operations Noncommissioned Officer

The manual became effective on May 15, 2006, but no specific date is given for implementing the 8431-to-0521 change in personnel records. July 20, 2006 is the announcement's publication date, not a confirmed conversion date.

Source extraction notes

The cited source prints the MOS code but not its occupational title; no title was inferred. Enlisted MOS moved from category 8000/9000 to a regular occupational field. The manual is effective 2006-05-15, but personnel/HRDP implementation is explicitly deferred, so effective_to is null. No row-specific effective date is printed; year-only precision reflects the 2006 manual transition.

Source documents (2)

Reviewed September 24, 2026 against references 1 and 2.

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.