At Kennedy Space Center, the work becomes visible for a moment. A rocket segment rises inside the Vehicle Assembly Building, a cavernous structure with its own weather. Technicians align hardware, test connections and prepare systems for a crewed trip around the Moon. Then the spotlight moves to the astronauts. Amentum, the company helping NASA process, assemble, test and launch that hardware, slips back into the machinery of the mission.
That is a useful way to understand Amentum. It lives in the long, difficult interval between a bold public goal and the day the system actually has to work. The Chantilly, Virginia company supports spacecraft and launch ranges, intelligence networks, military fleets, nuclear facilities, environmental cleanup sites and public infrastructure. Its name is less familiar than many of the agencies and prime manufacturers around it. Its fingerprints are everywhere.
The business of fewer surprises
Amentum calls itself an advanced engineering and technology company. The description is accurate, if incomplete. What customers really purchase is controlled complexity. A government can commission a new command system, nuclear facility or launch program. The harder task is coordinating thousands of technical decisions, cleared specialists, suppliers, safety rules and aging assets without losing the mission in the handoffs.
Amentum works those handoffs. Its Digital Solutions segment covers intelligence analytics, cybersecurity, space-system development and next-generation IT. Its Global Engineering Solutions segment handles nuclear power, environmental remediation, platform engineering, sustainment and supply chains. One side moves data through secure systems. The other moves people, parts and hazardous materials through the physical world. Together they let Amentum follow a program from design and testing into operation, modernization and eventual decommissioning.
A new company with old memory
The current company is young. Amentum launched independently in 2020 when AECOM sold its Management Services business to private-equity owners American Securities and Lindsay Goldberg. It then acquired DynCorp International, adding aviation and logistics depth, and PAE, a large federal-services operator. In September 2024, it combined with Jacobs' Critical Mission Solutions and Cyber & Intelligence businesses through a Reverse Morris Trust transaction. Three days later, shares began regular trading on the New York Stock Exchange under AMTM.
The corporate shell dates from this decade; the operating memory does not. Heritage teams have supported the Waste Isolation Pilot Plant in New Mexico since the mid-1980s. Other lineages run through Westinghouse, AECOM, PAE, DynCorp and Jacobs. That accumulation matters in markets where a safety record, a facility clearance and the engineer who remembers why a valve was specified in 1998 can be more defensible than a patent.
Amentum launches as an independent federal-services company and acquires DynCorp International.
The PAE acquisition adds diplomatic, intelligence and mission-support work; John Heller becomes CEO.
The Jacobs government-business combination creates today's Amentum, which lists on the NYSE.
Amentum enters the Fortune 500 as it expands in nuclear energy, space and critical digital infrastructure.
Who pays for reliability
The customer list explains the company better than any brand statement. In the United States it serves defense and intelligence organizations, the Department of Energy, NASA, the Department of Homeland Security and other agencies. Abroad, major customers include the UK Ministry of Defence, the UK Nuclear Decommissioning Authority and Australia's Department of Defence. Commercial work exists, especially in digital infrastructure and energy, but public missions remain the center of gravity.
Fiscal 2025 revenue was $14.393 billion. Defense and intelligence customers supplied $7.678 billion; other U.S. agencies supplied $3.994 billion. Commercial and international customers contributed $2.721 billion. In other words, a little more than 81 percent came from the U.S. government. That concentration brings durable demand and very large programs. It also ties Amentum to procurement cycles, appropriations, audits and shifting political priorities.
FY2025 revenue mix by customer
Contracts are the product wrapper
Amentum earns money through contracts rather than unit sales. Cost-plus-fee agreements, the largest part of its 2025 mix, reimburse allowable costs and add a fee. They fit programs whose scope can evolve, though margins are constrained and performance is closely scrutinized. Fixed-price work transfers more cost risk to the contractor in exchange for potential upside. Time-and-materials agreements bill labor and inputs at negotiated rates.
The company was the prime contractor on $13.096 billion of its $14.393 billion in fiscal 2025 revenue. That role gives it more responsibility for delivery and more influence over the program architecture. Backlog reached $47.1 billion at year end and $47.8 billion by April 2026. Backlog is not cash in the bank - portions depend on future funding, options and task orders - but it shows how far forward this industry can see.
What customers avoid
Fragmented vendors, unplanned downtime, unsafe transitions, obsolete systems, missing skills and costly failures at the boundaries between software and operations.
What Amentum assembles
Cleared talent, engineering disciplines, program controls, secure technology, facilities, supply chains and institutional memory under one accountable operator.
The strange adjacency advantage
The portfolio can look random: AI-assisted logistics in the Indo-Pacific, space-range operations, data-center retrofits, wildfire fleet analytics, nuclear submarine safety advice and radioactive-waste retrieval. The pattern appears when viewed through the customer's problem. Each job combines specialized technology with a high-consequence operating environment. Each rewards a contractor that understands both the system and the bureaucracy around it.
This distinguishes Amentum from a defense manufacturer whose economics depend on selling aircraft, missiles or sensors. It also separates the company from a conventional consultancy that can recommend a plan but may not operate the result for the next decade. Amentum competes most directly with Leidos, CACI, KBR, SAIC, Parsons, Peraton and other government-services groups. In nuclear and environmental work, it meets Bechtel, Fluor, AtkinsRéalis, BWX Technologies and Westinghouse. Its pitch is breadth without surrendering technical depth.
There is a practical lesson here. Integration becomes a moat when customers have too many interfaces. Amentum can combine data scientists, systems engineers, maintainers, safety specialists and program managers, then place that team inside a customer's mission for years. The technology is important. The rare capability is getting every discipline to arrive on the same Tuesday with the correct clearance and an agreed definition of done.
Nuclear, space and the next growth map
Management has pointed to nuclear energy, space systems and critical digital infrastructure as faster-growth markets. The logic is visible in recent awards. Rolls-Royce SMR selected Amentum to help deliver initial small modular reactors in Britain and the Czech Republic. The role covers integration, oversight, governance and construction management - precisely the connective work that becomes more valuable when a new technology meets real-world delivery.
In space, the company supports mission operations, launch ranges, test facilities and Artemis ground systems. In digital infrastructure, 2026 awards included secure wireless networks, data-center retrofits for AI workloads and continuous cyber monitoring. The common denominator is not a particular technology trend. It is public and private infrastructure becoming more complex while the tolerance for interruption keeps shrinking.
The risks are equally concrete. Government budgets move slowly until they move suddenly. Fixed-price work can punish estimation errors. Classified and hazardous programs leave little room for cultural drift. The 2024 combination also created a large integration job inside Amentum itself. A company that sells flawless handoffs must prove it can manage its own.
Scale is useful here, but it is not magic. A small specialist can move faster in a narrow technical field; a platform manufacturer can control the hardware roadmap; a strategy firm may reach senior decision-makers earlier. Amentum has to make its size feel like access rather than overhead. The company wins when a customer needs several of those capabilities at once, in multiple locations, under one performance regime. Its approximately 50,000 employees are not merely a head-count statistic. They are a distributed inventory of certifications, clearances, site knowledge and practiced routines. The commercial challenge is keeping that inventory current as missions change. The human challenge is retaining people whose expertise may exist nowhere else on the contract.
Where Amentum fits
Amentum sits between the makers of major platforms, the software specialists and the agencies that own the mission. It can design and modernize systems, but much of its value arrives after the ribbon cutting: operating, testing, sustaining, integrating and eventually retiring what others built. That is why the company can participate in both the nuclear resurgence and the cleanup of nuclear history.
Its mission statement names science, security and sustainability. Those words can sound broad enough to disappear. On the ground they describe a distinct collection of chores: help a spacecraft leave Earth, keep sensitive information protected, make an allied fleet ready, extend the life of a power station, retrieve dangerous waste. None makes a tidy consumer product. Together they make a large, durable business around the world's least tidy problems.