https://crsreports.congress.gov
Updated August 23, 2024
Defense Primer: Department of Defense Pre-Positioned Materiel
As part of its global posture, the Department of Defense
(DOD) maintains stocks of mission-essential equipment,
supplies, and munitions deemed sufficient to attain and
sustain strategic objectives in contingency plans. To
facilitate rapid deployment of U.S. forces during the initial
phases of operations, some of this materiel is pre-positioned
at or near points of planned use in specialized facilities (i.e.,
ashore) and dedicated ships (i.e., afloat).
Why does DOD pre-position materiel?
Pre-positioned war reserve materiel (PWRM) reduces
demand for strategic airlift and sealift assets by locating
heavy and bulky materiel closer to the theater of operations.
It sustains warfighters while supply lines are established
and the industrial base surges production. PWRM may also
be used to signal U.S. intentions. Materiel stored overseas
may demonstrate commitment to allies and partners or
enhance the deterrence of potential adversaries. As stated in
the Army Operations Field Manual (FM 3-0), a robust
PWRM inventory is essential to providing credible support
to partner forces during a crisis. Accordingly, enhanced pre-
positioning of equipment, munitions, fuel, and materiel is a
core focus of both the European Deterrence Initiative (EDI)
and Pacific Deterrence Initiative (PDI).
During Operation Desert Shield in 1990-1991, PWRM
enabled the delivery of Marine Corps armored units to the
Persian Gulf one month before the arrival of other armored
units shipped from the United States, according to the
Congressional Budget Office. In 2022, DOD PWRM
equipped U.S. forces supporting the NATO Response Force
following Russia’s invasion of Ukraine.
The effectiveness of large PWRM stocks, however, also
makes them potential priority targets for adversary long-
range weapons in conflict scenarios. Responding to such
challenges, DOD’s Joint Concept for Logistics envisions a
“comprehensive array” of large and small PWRM stocks
that can be selectively accessed and quickly shifted between
theaters of operations, even in contested environments. In
2023, DOD officials began referencing the incorporation of
prepositioned stocks into a “Global Positioning Network”
to enable persistent campaigning in the Indo-Pacific.
Responsibilities and Management
The Under Secretary of Defense for Acquisition and
Sustainment establishes and maintains a DOD-wide
strategic policy for WRM and PWRM. Combatant
Commanders (CCDRs) determine PWRM operational
requirements in accordance with strategic guidance; the
Joint Staff then reviews and validates these requirements.
Each military service (hereinafter “service”) maintains and
administers PWRM to satisfy such requirements and meet
the needs of CCDRs. The services rely upon the Defense
Logistics Agency and contractor support to maintain
PWRM, but may seek host nation support for some items.
Several sections of Title 10, U.S. Code (U.S.C.) govern
PWRM, including the following:
• 10 U.S.C. §2229. Requires the Secretary of Defense to
maintain a strategic policy on pre-positioned materiel
and to certify annually that current PWRM “meet all
operations plans, in both fill and readiness.”
• 10 U.S.C. §2390. Authorizes sale of PWRM to non-
DOD entities during declared international crisis.
Requires prompt replenishment of stocks.
• 10 U.S.C. §118b. The FY2021 National Defense
Authorization Act, as amended, requires DOD to submit
a classified report to Congress following publication of
a new National Defense Strategy detailing PWRM
requirements 5, 10, and 25 years into the future.
Funding
As with many other military functions for which DOD is
both a customer and key supplier, successful management
of DOD pre-positioned materiel involves both appropriated
funds from Congress and defense working capital funds that
purchase and manage inventories to stabilize item supplies
and prices.
Two defense appropriations primarily fund PWRM:
Operations and Maintenance (O&M) and Procurement.
Services use O&M funds for both the pre-positioned
materiel itself and the necessary expenses required to
operate humidity-controlled ashore facilities and ships
carrying afloat assets throughout the year. O&M PWRM
requirements are categorized as either mobilization or
operating forces requirements in DOD budget justifications.
Procurement budgets integrate PWRM requirements within
agency-wide requirements for a given weapon system. For
example, upgrades to a combat vehicle may include
procurements sufficient for “one Army Prepositioned Stock
[APS] brigade” along with four (non-PWRM) Armor
Brigade Combat Teams.
EDI and PDI budget exhibits summarize relevant DOD
PWRM activities. For FY2025, DOD requested $713
million for enhanced prepositioning for EDI.
Selected PWRM Programs
Army Pre-Positioned Stocks (APS)
The Army considers APS materiel “a cornerstone of the
Army’s ability to rapidly project power.” Army Materiel
Command (AMC) manages APS, while Army Sustainment
Command and other AMC subordinate commands maintain
the stocks through regional Army Field Support Brigades
and Battalions (see Figure 1). APS contain several
categories of materiel:
