An officer candidate school (OCS) is a military school which trains civilians and enlisted personnel in order for them to gain a commission as officers in the armed forces of a country. How OCS is run differs between countries and services. Typically, officer candidates have already attained post-secondary education, and sometimes a Bachelor's degree, and undergo a short duration of training (not more than a year) which focuses primarily on military skills and leadership. This is in contrast with a military academy which includes academic instruction leading to a bachelor's degree.
Officer Cadet School of Australia – Portsea (OCS Portsea) commenced training officers for the Australian Army in 1951 and continued through to the end of 1985. Since OCS Portsea's closure in 1985, all Australian Army Officer training has been conducted at the Royal Military College, Duntroon in Canberra. During the Vietnam War, the Officer Training Unit, Scheyville was used to train and commission National Servicemen as 2nd Lieutenants between 1965 and 1972.
In France training for officers is at: École polytechnique, École spéciale militaire de Saint-Cyr, École des officiers de la gendarmerie nationale, École navale, École de l'air, École militaire interarmes, École militaire supérieure d'administration et de management and École de santé des armées.
In Germany training for officers is at:
In the Philippines, the Armed Forces of the Philippines Officer Candidate School was originally formed out from the defunct School for Reserve Commission or SRC that was established in the 1930s pursuant to the provisions of then Philippine Commonwealth Act Number 1, otherwise known as "The National Defense Act of the Philippines". This was created in preparation for the defense of the Philippines, establishing a 10-year program of training for Filipino Servicemen and Civilian Volunteers (Reserve), and forming the Philippine Army as the main ground forces of the Armed Forces of the Philippines. A transfiguration took place with some military personnel from the Philippine Constabulary being transferred to form the nucleus of the Philippine Army. However, the 10-year program was incomplete by the time World War II broke out in the Pacific and ROSS training was subsequently stopped. Nevertheless, many of its trainees were called to active duty to serve throughout the war mainly with the U.S. Army Forces in the Far East (USAFFE).
The need for commissioned officers after the U.S. liberation of the Philippines in the 1940s prompted the establishment of the School for Reserve Commission, which later became the Officer Candidate School. Early training was held at Camp Tinio, Bangad, Cabanatuan City, Nueva Ecija, Nichols Air Base in Pasay and Fort Bonifacio in Metro Manila. Some graduates of these classes were sent to conflicts in both Korea and Vietnam. Later, the OCS training location was moved to Camp Capinpin, Tanay, Rizal from where 27 classes graduated between 1987 and 2005. Officer candidates with the rank of Probationary Second Lieutenant and Probationary Ensign have to undergo and pass the 12-month Officer Candidate Course before they can be commissioned as Regular and Reserve Officers in the Philippine Army, the Philippine Constabulary, the Philippine Air Force, the Philippine Navy and the Technical Service (Medical Administrative Corps and Women's Auxiliary Corps).
In 1993, OCS started accepting two foreign officer candidates from the Royal Brunei Armed Forces who joined the Officer Candidate Course "Balikatan" Class 12-94. In 1994, five female OCs belonging to AFPOCS "Balikatan" Class 12-94 graduated to become the first female officers of the AFP and were not included anymore as Women's Auxiliary Corps officers. Some Filipino officer candidates were also sent to train in Australia, New Zealand, Singapore and the United Kingdom. Today, each of the three armed services of the Armed Forces of the Philippines (AFP) – Army, Air Force and Navy – run their own officer training in separate locations such as Philippine Air Force Aviation OCS in Fernando Air Base, Lipa City; Philippine Army OCS in Camp O'Donnell, Capas, Tarlac; and Philippine Navy OCS in San Antonio, Zambales.
In Singapore, Officer Cadet School (OCS) is a school within SAFTI Military Institute, which serves as the main center for training officers of all ranks. OCS is a tri-service institution which trains officers of the Army, Navy, and Air Force. Unlike other countries, OCS is the only route to a commission in the SAF. Even selected cadets who hold scholarships to train in friendly service academies must complete two thirds of OCS and receive their commission before undergoing further training overseas.
OCS in Singapore lasts approximately 38 weeks. The first term consists of military knowledge applicable to all services, including military history and military law. Subsequently, Officer Cadets are streamed into their services based on aptitude and personal preference, and receive training specific to their service.
In South Korea, Officer Candidate School (학사사관) were modeled on OCS programs of the United States Armed Forces. Qualified persons may earn a commission by passing rigorous basic combat training lasting 3 to 4 months.
The Republic of Korea Army has the highest number of officer candidates each year. All applicants must hold bachelor's degree, unless they are currently non-commissioned officers in active duty, or hold specialized certifications or licenses, such as doctors and attorneys. Most applicants will take a written exam, physical tests, and several interviews for consideration. Admitted applicants are ordered enlistment in the Army Cadet Military School in Goesan. At graduation, candidates earn a commission with the rank of Second Lieutenant.
The Republic of Korea Navy and the Republic of Korea Marine Corps have maintained the most rigorous candidate school program in South Korea. Both ROKN and ROKMC officer candidates earn commissions together at Republic of Korea Naval Academy in Changwon, while their training programs are distinct. ROKMC candidates will be sent to Marine Corps School in Pohang, while ROKN candidates remain in Changwon. Petty officers in active duty who have earned the bachelor's degree may also apply to the OCS program.
The Republic of Korea Air Force's Officer Training School (OTS) is a popular and competitive officer training program in South Korea. ROKAF OTS trains the majority of its candidates for air defense forces and military police. While OTS also trains pilots, the majority of ROKAF pilots come from the Air Force Academy or ROKAF ROTC programs.
The Royal Military Academy Sandhurst (RMAS), commonly known as Sandhurst, is the British Army's initial officer training centre and is located in the town of Camberley, near the village of Sandhurst, Berkshire, England, about 55 kilometres (34 mi) southwest of London. The Academy's stated aim is to be "the national centre of excellence for leadership." All British Army officers, including late-entry officers who were previously Warrant Officers, as well as many other men and women from overseas, are trained at Sandhurst. The Academy is the British Army equivalent of the Britannia Royal Naval College Dartmouth, Royal Air Force College Cranwell, and the Commando Training Centre Royal Marines.
In the United States Armed Forces, Officer Candidate School (OCS) or the equivalent is a training program for college graduates and non-commissioned officers, soldiers, sailors, marines, airmen and coast guardsmen to earn commissions as officers. The courses generally last from six to seventeen weeks and include classroom instruction in military subjects, physical training, and leadership.
People may earn a commission in the United States Armed Forces through OCS or OTS, by staff appointment, through Reserve Officers Training Corps (ROTC), or through one of the five federal service academies.