Pentagon adopts three-tiered approach to enforce modular open systems
The Defense Department will implement a three-tiered strategy to ensure modular open systems approach (MOSA) is adopted across military branches, a defense official said. The plan follows the Acquisition Transformation Strategy introduced by Defense Secretary Pete Hegseth in November. It aims to accelerate MOSA adoption across all Portfolio Acquisition Executive offices.
The three-tiered strategy is designed to push modular open systems adoption down to individual program offices, ensuring the approach is consistently applied rather than left to chance. Matt Sipe, who leads the Pentagon's MOSA Cadre, confirmed the plan follows the broader Acquisition Transformation Strategy that Secretary Pete Hegseth introduced in November, which restructured acquisition leadership through the new Portfolio Acquisition Executive system.
The PAE structure is central to this effort, with MOSA acceleration now formally assigned across all portfolio executives. This represents a shift toward standardizing open architecture requirements across military branches, with the intent of making interoperability and upgradeability routine expectations in new weapons systems rather than exceptions.
The push for modular open systems could affect defense contractors and taxpayers alike. If implemented consistently, it may reduce long-term costs by making systems easier to upgrade and less dependent on proprietary vendors. However, it could also disrupt established supply chains and require significant retraining across acquisition offices. The success of this strategy may ultimately shape how quickly the military can field new capabilities, which has implications for national security readiness.