The Military Health System (MHS) is the comprehensive healthcare organization within the U.S. Department of Defense, serving uniformed service members, retirees, and their families worldwide. It is recognized as one of the largest and most complex integrated healthcare systems globally, distinct from typical civilian insurance or provider networks. The MHS provides a full spectrum of medical services, ranging from field casualty care to primary care and specialized surgical procedures. This expansive system manages a budget of over $50 billion and serves approximately 9.5 million eligible beneficiaries across the globe. The MHS structure prioritizes the health of the fighting force while delivering a comprehensive benefit to its members.
Defining the Scope and Mission
The Military Health System operates under a dual mission that governs its structure and operational choices worldwide. Its foremost responsibility is medical readiness, ensuring that the armed forces are healthy, fit, and prepared to deploy and sustain military operations anywhere on the globe. This mission requires the MHS to maintain a ready medical force, meaning that medical personnel and assets must be trained and equipped to provide care in both conventional hospitals and austere operational environments.
The second mission is the delivery of a comprehensive healthcare benefit to all eligible service members, retirees, and their families. This healthcare delivery mission provides a medical benefit commensurate with the service and sacrifice of military personnel, ensuring access to quality care both domestically and internationally. Military treatment facilities prioritize maintaining the clinical skills of military medical staff to ensure they are prepared for combat casualty care. The MHS integrates health care delivery with medical education, public health, and medical research to support these two primary goals.
Categories of Beneficiaries
The Military Health System extends its healthcare benefit to a diverse group of individuals, whose eligibility is tracked through the Defense Enrollment Eligibility Reporting System (DEERS). The primary category consists of Active Duty Service Members (ADSMs) and their eligible family members, who have the highest priority for accessing care within military facilities. This group includes personnel from the Army, Navy, Air Force, Marine Corps, and Coast Guard, as well as the commissioned corps of the Public Health Service and the National Oceanic and Atmospheric Administration.
Another significant group is the Reserve Component members, which includes the National Guard and Reserves, along with their families. Their eligibility for the MHS benefit can fluctuate based on their duty status; they receive the same full benefit as active duty members when they are activated for service. Retired service members and their eligible family members also constitute a large portion of the beneficiary population. Eligibility also covers other groups, such as Medal of Honor recipients and certain former spouses.
Administrative Structure and Infrastructure
The administrative oversight and execution of the Military Health System are highly centralized and managed primarily by the Defense Health Agency (DHA). The DHA is a joint, integrated combat support agency that acts as the central orchestrator for MHS operations and clinical business across the Department of Defense. It integrates the medical services of the Army, Navy, and Air Force to provide a medically ready force and a ready medical force to combatant commands.
The DHA manages a global network of Military Treatment Facilities (MTFs), which serve as the physical infrastructure of the MHS’s “Direct Care” system. This network includes medical centers, hospitals, and ambulatory care clinics, totaling over 700 facilities worldwide. Since 2017, Congress directed the consolidation of all DoD MTFs under the DHA, centralizing the management of these facilities. The DHA is also responsible for operating the electronic health record system, MHS GENESIS, to ensure seamless digital connectivity across the entire global system.
The agency operates under the authority and oversight of the Assistant Secretary of Defense for Health Affairs, a civilian official who serves as the chief medical adviser and directs health policy and budgeting. This structure ensures that the military medical departments and the MTFs operate under a unified command for healthcare delivery, while the individual military services maintain responsibility for the operational readiness of their medical personnel.
Healthcare Access Through TRICARE
Healthcare access for MHS beneficiaries is primarily facilitated through the TRICARE program, which functions as the insurance component of the system. TRICARE provides a comprehensive and affordable health benefit to millions of military families, past and present. The program utilizes a two-part approach to care delivery: the Direct Care system and the Purchased Care system.
The Direct Care system refers to medical and dental services received at Military Treatment Facilities (MTFs), staffed by uniformed and civilian government personnel. The Purchased Care system is the network of civilian healthcare providers, hospitals, and pharmacies that contract with TRICARE to provide care to beneficiaries. The MHS purchases over 65% of the total care provided to beneficiaries through this civilian network.
TRICARE offers several plan options that dictate how beneficiaries access care and what their cost-sharing responsibilities are. TRICARE Prime is a managed care option, similar to a civilian Health Maintenance Organization (HMO), where beneficiaries are assigned a Primary Care Manager (PCM) and typically receive most of their care at an MTF.
TRICARE Select is a self-managed, Preferred Provider Organization (PPO)-style option that offers flexibility to see any authorized provider without a required PCM or referrals for most services. For Medicare-eligible retirees and their families, TRICARE For Life acts as a secondary payer, or Medicare wraparound, ensuring virtually no out-of-pocket costs when beneficiaries are also enrolled in Medicare Parts A and B.