The organisation of a military health system (MHS) differs from the civilian system due to the role of the armed forces, the unique nature of the supported population and their occupational health requirements. A previously published review of the Military Medical Corps Worldwide Almanac demonstrated the value of a standardised framework for evaluation and comparison of MHSs. This paper proposes such a framework which highlights the unique features of MHSs not covered by health services research of national health systems. These include: national context and summary; organisational structure; firm base facilities, healthcare beneficiaries and medical research; operational capabilities, overseas deployments, collaborations and alliances; personnel including recruitment, training and education; and history and culture. This common framework can help facilitate international collaboration between military medical services including capability development, training exercises and mutual support during military operations. It can also inform national contributions to future editions of the Almanac.