Protective sign in the context of "Military surgeon"

The Army Medical Service (German: Sanitätsdienst Heer or Sanitätsdienst des Heeres) is a non-combat specialty branch of the German Army traditionally responsible for providing medical services within the army, and which has a humanitarian function during armed conflicts in accordance with international humanitarian law, and specific rights and responsibilities under the Geneva Conventions, their additional protocols and customary international humanitarian law. It is entitled under international humanitarian law to use the red cross as a protective sign and its personnel are protected persons under international humanitarian law. Since 2002, most of its former responsibilities have been transferred to the Joint Medical Service. The Army Medical Service still exists as a small entity within the German military.

Under the Geneva Conventions, the emblems of the International Red Cross and Red Crescent Movement are to be worn by all medical and humanitarian personnel and also displayed on their vehicles and buildings while they are in an active warzone, and all military forces operating in an active warzone must not attack entities displaying these emblems. The International Red Cross and Red Crescent Movement recognizes four protection emblems, three of which are in use: the Red Cross (recognized since 1864), the Red Crescent (recognized since 1929), the Red Lion and Sun (recognized since 1929; unused since 1980), and the Red Crystal (recognized since 2005).

The Red Cross was the original protection symbol declared at the First Geneva Convention in 1864. The Red Crescent, which was first used by the Ottoman Empire in the 1870s, and the Red Lion and Sun, which had been used only in Iran between 1924 and 1980, were both formally recognized as protection symbols following a 1929 amendment to the Geneva Conventions. Controversy stemming from the movement's successive rejections of the Red Star of David, which was established in 1899 and has been used only in Israel, led to the creation of the Red Crystal as the fourth protection symbol by a vote in 2005. In 2006, the movement announced that it was officially adopting the Red Crystal as a neutral symbol and that it was also granting formal recognition to Israel's Magen David Adom alongside the Palestine Red Crescent Society.

The term military medicine has a number of potential connotations. It may mean:

• A medical specialty, specifically a branch of occupational medicine attending to the medical risks and needs (both preventive and interventional) of soldiers, sailors and other service members. This disparate arena has historically involved the prevention and treatment of infectious diseases (especially tropical diseases), and, in the 20th century, the ergonomics and health effects of operating military-specific machines and equipment such as submarines, tanks, helicopters and airplanes. Undersea and aviation medicine can be understood as subspecialties of military medicine, or in any case originated as such. Few countries certify or recognize "military medicine" as a formal speciality or subspeciality in its own right.
• The planning and practice of the surgical management of mass battlefield casualties and the logistical and administrative considerations of establishing and operating combat support hospitals. This involves military medical hierarchies, especially the organization of structured medical command and administrative systems that interact with and support deployed combat units. (See Battlefield medicine.)
• The administration and practice of health care for military service members and their dependents in non-deployed (peacetime) settings. This may (as in the United States) consist of a medical system paralleling all the medical specialties and sub-specialties that exist in the civilian sector. (See also Veterans Health Administration which serves U.S. veterans.)
• Medical research and development specifically bearing upon problems of military medical interest. Historically, this encompasses all of the medical advances emerging from medical research efforts directed at addressing the problems encountered by deployed military forces (e.g., vaccines or drugs for soldiers, medical evacuation systems, drinking water chlorination, etc.) many of which ultimately prove important beyond the purely military considerations that inspired them.

Protected persons is a legal term under international humanitarian law and refers to persons who are under specific protection of the 1949 Geneva Conventions, their 1977 Additional Protocols, and customary international humanitarian law during an armed conflict.

The legal definition of different categories of protected persons in armed conflicts is found in each of the 1949 Geneva Conventions and in the 1977 Additional Protocols. The extent of protection and obligations of belligerent states and parties depends on the type of the armed conflict (international or not international) as well as on the category of protected persons in terms of their age (adult/child), sex (man/woman), participation in the armed conflict (combatant/prisoner of war/civil person) and personal situation (e.g. shipwrecked, sick, wounded, and etc.).

Civil defense or civil protection is an effort to protect the citizens of a state (generally non-combatants) from human-made and natural disasters. It uses the principles of emergency management: prevention, mitigation, preparation, response, or emergency evacuation and recovery. Programs of this sort were initially discussed at least as early as the 1920s and were implemented in some countries during the 1930s as the threat of war and aerial bombardment grew. Civil-defense structures became widespread after authorities recognised the threats posed by nuclear weapons.

Since the end of the Cold War, the focus of civil defense has largely shifted from responding to military attack to dealing with emergencies and disasters in general. The new concept is characterised by a number of terms, each of which has its own specific shade of meaning, such as crisis management, emergency management, emergency preparedness, contingency planning, civil contingency, civil aid and civil protection.

Protocol III (also Additional Protocol III or AP III) is a 2005 amendment protocol to the Geneva Conventions relating to the Adoption of an Additional Distinctive Emblem. Under the protocol, the protective sign of the Red Crystal may be displayed by medical and religious personnel at times of war, instead of the traditional Red Cross or Red Crescent symbols. People displaying any of these protective emblems are performing a humanitarian service and must be protected by all parties to the conflict.