What is the difference between field and sustainment?

• A. Field: green suiters fix; Sustainment: send stuff back to manufacturer to get fixed
• B. Field: on-site repairs by unit maintenance; Sustainment: off-site repairs at factory
• C. Field: supply replenishment; Sustainment: medical support
• D. Field: long-term procurement; Sustainment: short-term repairs

Answer: (A)

Field maintenance is the in-theater, on-site work done by unit maintenance personnel to keep gear operational through quick fixes and routine servicing. Sustainment maintenance handles more complex issues and typically takes the equipment off-site to a depot or back to the manufacturer for repair, restoring the item to full capability. The description that field maintenance is performed by soldiers in the field while sustainment involves sending gear back to the manufacturer for repair captures this higher-to-lower echelon flow of repair and aligns with how sustainment supports long-term readiness.