This article has multiple issues. Please help improve it or discuss these issues on the talk page. ( Learn how and when to remove these template messages)( Learn how and when to remove this template message)
In its broadest sense, the term "officer" refers to non-commissioned officers and warrant officers. However, when used without further detail, the term almost always refers to commissioned officers, the more senior portion of a force who derive their authority from a commission from the head of state.
- 1 Numbers
- 2 Legal relevance
3 Commission Sources and Training
- 3.1 United Kingdom
3.2 United States
- 3.2.1 Terminological details in the U.S.
- 3.2.2 Service Academies
- 3.2.3 Reserve Officers' Training Corps (ROTC)
- 3.2.4 Federal Officer Candidate Schools
- 3.2.5 Marine Corps Platoon Leaders Class (PLC)
- 3.2.6 National Guard OCS
- 3.2.7 Early Commissioning Programs
- 3.2.8 Direct Commission
- 3.2.9 Discontinued
- 3.3 Commonwealth of Nations
- 4 Warrant officers
- 5 Non-commissioned officers
- 6 Officer ranks and accommodation
- 7 See also
- 8 References
- 9 External links
The proportion of officers varies greatly. Commissioned officers typically make up between an eighth and a fifth of modern armed forces personnel. In 2013, officers were the senior 17% of the British armed forces,  and the senior 13.7% of the French armed forces.  In 2012, officers made up about 18% of the German armed forces,  and about 17.2% of the United States armed forces. 
Historically, however, armed forces have generally had much lower proportions of officers. During the First World War, fewer than 5% of British soldiers were officers (partly because World War One junior officers suffered very high casualty rates). In the early twentieth century, the Spanish army had the highest proportion of officers of any European army, at 12.5%, which was at that time considered unreasonably high by many Spanish and foreign observers.
Within a nation's armed forces, armies (which are larger) tend to have a lower proportion of officers, but a higher total number of officers, while navies and air forces have higher proportions of officers, especially since military aircraft are flown by officers. For example, 13.9% of British army personnel and 22.2% of the RAF personnel were officers in 2013, but the army had a larger total number of officers. 
Having a command authority is one requirement for combatant status under the laws of war, though this authority need not have obtained an official commission or warrant.  In such case, those persons holding offices of responsibility within the organization are deemed to be the officers, and the presence of these officers connotes a level of organization sufficient to designate a group as being combatant.
Commissioned officers generally receive training as leadership and management generalists, in addition to training relating to their specific military occupational specialty or function in the military. Many advanced militaries require university degrees as a prerequisite for commissioning, even from the enlisted ranks. Others, including the Australian Defence Force, the British Armed Forces (BAF), Nepal Army, the Pakistani Armed Forces (PAF), the Swiss Armed Forces, the Singapore Armed Forces, the Israel Defense Forces (IDF), the Swedish Armed Forces, and the New Zealand Defence Force, are different in not requiring a university degree for commissioning—although a significant number of officers in these countries are graduates. In the Israel Defense Forces, a university degree is a requirement for an officer to advance to the rank of lieutenant colonel. The IDF often sponsors the studies for its majors, while aircrew and naval officers obtain academic degrees as a part of their training programmes.
In the United Kingdom, there are three routes of entry for British Armed Forces officers. The first, and primary route are those who receive their commission directly into the officer grades following completion at their relevant military academy. In the second method, an individual may gain their commission after first enlisting and serving in the junior ranks, and typically reaching one of the senior non-commissioned officer ranks (which start at sergeant (Sgt), and above), as what are known as 'direct entry' or DE officers (and are typically and informally known as an 'ex-ranker'). The third route is similar to the second, in that they convert from an enlisted to a commission; but these are only taken from the highest ranks of SNCOs, and are known as 'late entry' or LE officers. LE officers, whilst holding the same Queen's commission, generally work in different roles from the DE officers. In the infantry, a number of warrant officer class 1s are commissioned as LE officers.
In the British Army, commissioning for DE officers occurs after a 44-week course at the Royal Military Academy Sandhurst for regular officers or the Army Reserve Commissioning Course, which consists of four two-week modules (A-D) for Army Reserve officers. The first two modules may be undertaken over a year for each module at an Officers' Training Corps, the last two must be undertaken at Sandhurst. For Royal Navy and Royal Air Force officer candidates, a 30-week period at Britannia Royal Naval College or a 24-week period at RAF College Cranwell, respectively. Royal Marines officers receive their training in the Command Wing of the Commando Training Centre Royal Marines during a gruelling 15-month course. The courses consist of not only tactical and combat training, but also leadership, management, etiquette, and international affairs training.
Commissioned officers are typically the only persons, in an armed forces environment, able to act as the commanding officer (according to the most technical definition of the word) of a military unit.  A superior officer is an officer with a higher rank than another officer, who is a subordinate officer relative to the superior.
Non-commissioned officers (NCOs), to include naval and coast guard petty officers and chief petty officers, in positions of authority can be said to have control or charge rather than command per se (although the word "command" is often used unofficially to describe any use of authority).
Most officers in the Armed Forces of the United States are typically commissioned through one of three major commissioning programs:
- United States Military Academy (USMA) (commissions 2nd Lieutenants in the US Army)
- United States Naval Academy (USNA) (commissions both Ensigns in the US Navy and 2nd Lieutenants in the US Marine Corps)
- United States Air Force Academy (USAFA) (commissions 2nd Lieutenants in the US Air Force)
- United States Coast Guard Academy (USCGA) (commissions Ensigns in the US Coast Guard)
- United States Merchant Marine Academy (USMMA) (commissions Ensigns in the US Navy Reserve; graduates may apply for active duty in the US Navy)
Graduates of the United States service academies attend their institutions for no less than four years and, with the exception of the USMMA, are granted active-duty commissions immediately upon completion of their training. They make up approximately 20% of the U.S. armed forces officer corps.
In addition to the service academies, officers in the U.S. Armed Forces may also be commissioned through the Reserve Officers' Training Corps (ROTC), which is by far the largest source of officers for the U.S. Army and the U.S. Air Force during peacetime:
- Army ROTC
- Naval ROTC (commissions both Ensigns in the US Navy and 2nd Lieutenants in the US Marine Corps)
- Air Force ROTC
ROTC is composed of small training programs at several hundred American colleges and universities.  There is no Marine Corps ROTC program per se, but there exists a Marine Corps Option for selected midshipmen in the Naval ROTC programs at civilian colleges and universities or at non-Federal military colleges such as The Citadel and the Virginia Military Institute. 
In addition to the service academies and ROTC, officers in the U.S. armed forces may also be commissioned via Officer Candidate programs for college graduates:
A smaller number of officers may be commissioned via other programs, such as the Marine Corps Platoon Leaders Class (PLC) during summers while attending college. PLC is a sub-element of Marine Corps OCS and college and university students enrolled in PLC undergo military training at Marine Corps Officer Candidate School in two segments: the first of six weeks between their sophomore and junior year and the second of seven weeks between their junior and senior year. There is no routine military training during the academic year for PLC students as is the case for ROTC cadets and midshipmen, but PLC students are routinely visited and their physical fitness periodically tested by Marine Corps Officer Selection Officers (OSOs) from the nearest Marine Corps officer recruiting activity. PLC students are placed in one of three general tracks: PLC-Air for prospective Marine Naval Aviators and Marine Naval Flight Officers; PLC-Ground for prospective Marine infantry, armor, artillery and combat support officers; and PLC-Law, for prospective Marine Corps judge advocate general officers. Upon graduation from college, PLC students are commissioned as active duty 2nd Lieutenants in the US Marine Corps Reserve, with the option to augment their commissions to the Regular Marine Corps after five to ten years of commissioned service.
In addition to ROTC, Army National Guard (ARNG) officers may also be commissioned through state-based Officer Candidate Schools. These schools train and commission college graduates, prior-servicemembers, and enlisted Guard soldiers specifically for the National Guard.
In the United States Armed Forces, officers without a four-year university degree at the bachelor's level can, under certain circumstances, also be commissioned. In the Navy, Marine Corps and Coast Guard, these are typically the officers in the Limited Duty Officer (LDO) and Chief Warrant Officer (CWO) programs. Officers in this category constitute less than 2% of all officers.
Graduates of junior military colleges can also be commissioned with 2-year associate degrees, conditioned on subsequently completing a 4-year bachelor's degree within a defined time.
The Air Force, in contrast, now requires all commissioned officers, regardless of background or enlisted rank, to possess a minimum of a bachelor's degree prior to commissioning.
Direct commission is another route to becoming a commissioned officer. Credentialed civilian professionals such as scientists, pharmacists, physicians, nurses, clergy, and attorneys are directly commissioned upon entry into the military or another federal uniformed service. However, these officers generally do not exercise command authority outside of their specific branches (e.g., U.S. Army Medical Corps; U.S. Navy Judge Advocate General's Corps, etc.).
Although significantly represented in the retired senior commissioned officer ranks of the US Navy, a much smaller cohort of current active duty and active Reserve officers (all of the latter being Captains or Flag Officers as of 2017) were commissioned via the Navy's since discontinued Aviation Officer Candidate School (AOCS) program for college graduates. AOCS focused on producing line officers for Naval Aviation who would become Naval Aviators and Naval Flight Officers upon completion of flight training, followed by a smaller cohort who would become Naval Air Intelligence Officers and Aviation Maintenance Duty Officers. Designated as Aviation Officer Candidates (AOCs), individuals in the AOCS program were primarily non-prior military service college graduates, augmented by a smaller cohort of college-degreed Active Duty, Reserve or former enlisted personnel. In the late 1970s, a number of Air Force ROTC graduates who had lost their flight training slots prior to going on active duty due to a post-Vietnam Reduction in Force (RIF) resigned their inactive USAF commissions and also attended AOCS for follow-on naval flight training. AOCs were active duty personnel in pay grade E-5 (unless having held a higher Active Duty or Reserve enlisted grade) for the duration of their 14-week program. Upon graduation, they were commissioned as Ensigns in the then- US Naval Reserve on Active Duty, with the option to augment their commissions to the Regular Navy after 4 to 6 years of commissioned service.
AOCS also included the embedded Aviation Reserve Officer Candidate (AVROC) and Naval Aviation Cadet (NAVCAD) programs. AVROC was composed of college students who would attend officer training in two segments similar to Marine Corps PLC, but would do so between their junior and senior year and again following graduation, receiving their commission upon completion of the second segment. NAVCADs were enlisted personnel who held associate degrees, but lacked bachelor's degrees. NAVCADs would complete the entire AOCS program, but would not be commissioned until completion of flight training and receiving their wings. After their initial operational tour, they would be assigned to a college or university full-time for no more than two years in order to complete their bachelor's degree. AVROC and NAVCAD were discontinued when AOCS was merged into OCS in the mid-1990s.
Another discontinued commissioning program is the Air Force's Aviation Cadet program. Originally created by the US Army Signal Corps in 1907 to train pilots for its then-fledgling aviation program, it was later used by the subsequent US Army Air Service, US Army Air Corps and US Army Air Forces to train pilots, navigators, bombardiers and observers through World War I, the interwar period, World War II, and the immediate postwar period between September 1945 and September 1947. With the establishment of the US Air Force as an independent service in September 1947, it then became a source for USAF pilots and navigators. Cadets had to be between the ages of 19 and 25 and possess either at least two years of college/university level education or three years of a scientific or technical education. In its final iteration, cadets received the pay of enlisted pay grade E-5 and were required to complete all pre-commissioning training and flight training before receiving their wings as pilots or navigators and their commissions as 2nd Lieutenants on active duty in the US Air Force Reserve on the same day. Aviation cadets were later offered the opportunity to apply for a commission in the Regular Air Force and attend a college or university to complete a 4-year degree. As the Air Force's AFROTC and OTS programs began to grow, and with the Air Force's desire for a 100% college-degreed officer corps, the Aviation Cadet program was slowly phased out. The last Aviation Cadet Pilot graduated in October 1961 and the last Aviation Cadet Navigators in 1965. By the 1990s, the last of these officers had retired from the active duty Regular Air Force, the Air Force Reserve and the Air National Guard.
In countries whose ranking systems are based upon the models of the British Armed Forces (BAF), officers from the rank of Second Lieutenant (army), Sub-Lieutenant (navy) or Pilot Officer (air force) to the rank of General, Admiral or Air Chief Marshal respectively, are holders of a commission granted to them by the appropriate awarding authority. In United Kingdom (UK) and other Commonwealth realms, the awarding authority is the monarch (or a Governor General representing the monarch) as head of state. The head of state often is granted the power to award commissions, or has commissions awarded in his or her name.
In Commonwealth nations, commissioned officers are given commissioning scrolls (also known as commissioning scripts) signed by the Sovereign or the Governor General acting on the monarch's behalf. Upon receipt, this is an official legal document that binds the mentioned officer to the commitment stated on the scroll.
Non-commissioned members rise from the lowest ranks in most nations. Education standards for non-commissioned members are typically lower than for officers (with the exception of specialised military and highly-technical trades; such as aircraft, weapons or electronics engineers). Enlisted members only receive leadership training after they are promoted to positions of responsibility, or as a prerequisite for such. In the past (and in some countries today but to a lesser extent), non-commissioned members were almost exclusively conscripts, whereas officers were volunteers.
In some branches of many armed forces, there exists a third grade of officer known as a warrant officer. In the armed forces of the United States, warrant officers are initially appointed by the Secretary of the service and then commissioned by the President of the United States upon promotion to chief warrant officer. In many other countries (as in the armed forces of the Commonwealth nations), warrant officers often fill the role of very senior non-commissioned officers. Their position is affirmed by warrant from the bureaucracy directing the force—for example, the position of regimental sergeant major in regiments of the British Army is held by a warrant officer appointed by the British government.
In the U.S. military, a warrant officer is a technically-focused subject matter expert, such as helicopter pilot or information technology specialist. There are no warrant officers in the U.S. Air Force; the last warrant officers retired in the 1980s, and ranks became dormant. All other U.S. Armed Forces have warrant officers, with warrant accession programs unique to each individual service's needs. Although Warrant Officers normally have more years in service than regular commissioned officers, they are below regular commissioned officers in the rank hierarchy. In certain instances, commissioned chief warrant officers can command units.
A non-commissioned officer (NCO) is an enlisted member of the armed forces holding a position of some degree of authority who has (usually) obtained it by advancement from within the non-commissioned ranks. Officers who are non-commissioned usually receive management and leadership training, but their function is to serve as supervisors within their area of trade specialty. Senior NCOs serve as advisers and leaders from the duty section level to the highest levels of the armed forces establishment, while lower NCO grades are not yet considered management specialists. The duties of an NCO can vary greatly in scope, so that an NCO in one country may hold almost no authority, while others such as the United States and the United Kingdom consider their NCOs to be "the backbone of the military" due to carrying out the orders of those officers appointed over them. 
In most maritime forces (navies and coast guards), the NCO ranks are called petty officers while enlisted ranks prior to attaining NCO/petty officer status typically known as seaman, or some derivation thereof. In most traditional infantry, marine and air forces, the NCO ranks are known as sergeants and corporals, with non-NCO enlisted ranks referred to as privates and airmen.
However, some countries use the term commission to describe the promotion of enlisted soldiers, especially in countries with mandatory service in the armed forces. These countries refer to their NCOs as professional soldiers, rather than as officers.
Officers in nearly every country of the world are segregated from the enlisted soldiers, sailors, airmen, marines and coast guardsmen in many facets of military life. Facilities accommodating needs such as messing (i.e., mess hall or mess deck versus officers mess or wardroom), separate billeting/berthing, domiciles, and general recreation facilities (officer clubs versus NCO Clubs and CPO Clubs versus enlisted clubs) are separated between officers and enlisted personnel. This class system, historically correlated to socioeconomic status, is focused on discouraging fraternization and encouraging professional and ethical relations between officers and enlisted military personnel. 
Officers do not routinely perform physical labor; they typically supervise enlisted personnel doing so, either directly or via non-commissioned officers. Commissioned officers will and do perform physical labor when operationally required to do so, e.g., in combat. However, it would be very unusual for an officer to perform physical labor in garrison, at home station or in homeport.
- Officer (disambiguation)
- Direct commission officer
- Exchange officer
- List of comparative military ranks
- Mustang officer
- Staff officer
- Roving commission
- Foreign service officer
- "UK Armed Forces Annual Personnel Report" (PDF). Ministry of Defence. 1 April 2013. Retrieved 25 December 2015.
- "Défense : Jean-Yves Le Drian supprime 580 postes d'officiers de l'armée française en 2013". Latribune.fr. Retrieved 2017-08-20.
- Pike, John. "Germany - Military Personnel". Globalsecurity.org. Retrieved 2017-08-20.
- "2012 Demographics Report" (PDF). Militaryonesource.mil. Retrieved 2017-08-20.
- "Practice Relating to Rule 4. Definition of Armed Forces". International Committee of the Red Cross. Retrieved 5 July 2018.
- "10 U.S.C. § 101". US Congress. 5 January 2009.
- "Archived copy". Archived from the original on 3 December 2009. Retrieved 23 November 2011.CS1 maint: Archived copy as title ( link) CS1 maint: Unfit url ( link)
- "Leatherneck: Citadel "Double Dogs"" (PDF). Citadelsanantonio.org. Marine Corps Association. Archived from the original (PDF) on 12 August 2015. Retrieved 13 November 2015.
- "Direct Commission Selected School (DCSS) Program". Gocoastguard.com/. U. S. Coast Guard. Retrieved 2015-11-17.
- "Officer Candidate School (OCS)". Gocoastguard.com. Retrieved 2017-08-20.
- NCOs are 'backbone' of the Army, US Army Public Affairs Office, Fort Monmouth, NJ, 15 April 2009
- Fraternization Policy Update Reflects Current Operational Tempo, US Navy Chief of Naval Personnel Diversity Directorate, 26 May 2007
|Wikimedia Commons has media related to Military officers.|