Officer Candidates School ( United States Marine Corps ) The United States Marine Corps Officer Candidates School ( OCS ) is the entry - level training for Marine officers , equivalent to recruit training for enlisted Marines . Located at Marine Corps Base Quantico , the school trains , screens , and evaluates potential Marine Corps officers . Unlike the other United States military services , the majority of Marine Corps officers complete OCS to earn a commission ; the exceptions are midshipmen from the United States Naval Academy , limited duty officer s , and inter - service transfers . Depending on the source , Officer Candidate s go through either a 10 - week , or two 6 - week courses over separate summers , designed primarily to screen and evaluate candidates ' fitness to lead Marines by placing them in leadership positions in a stressful environment . Students are evaluated during 2 - 3 day garrison command billets at the company and platoon level , and squad and fire - team level tactical billets during field exercises . History . Prior to World War I , Marine officers came primarily from the Naval Academy , or were commissioned from the enlisted ranks . But as the Marine Corps expanded , it needed its own training pipeline for officers . OCS traces its roots to the " School of Application " , established in 1891 in Washington , D . C . With the expansion of the Marine Corps for World War I , all instructional efforts were consolidated in MCB Quantico , where they remain today . Location . OCS is currently located at Brown Field at Marine Corps Base Quantico . The Platoon Leaders Class Juniors was at Camp Upshur until 1986 , but was subsequently consolidated with the seniors at Brown Field . Selection and entry . Entry to the Officer Candidates School comes from several different commissioning programs : Officer Candidates must pass a series of tests before being admitted into the Officer Candidate School . An Officer Selection Officer , usually a Captain , meets with a prospective Officer Candidate . Upon completing a satisfactory interview , the OSO then makes the decision to move the prospective candidate onto the next step . The prospective candidate then must complete a short essay about why he wants to be a Marine Officer , provide identification ( usually a birth certificate and Social Security card ) , pass a background check , provide five letters of recommendation , and complete a physical medical exam . After successful completion of these steps , the OSO may then conduct the Officer Candidate through a Physical Fitness Test . Upon reaching a score on the test that the OSO deems to be acceptable ( usually in the range of 285 and above ) , the Officer Candidate then signs the contract ( including the contract to attend the course , the fraternization policy acknowledgement , and the Marine Corps drug policy acknowledgement ) . Candidates choose to enter the program as either a ground , air , or law contract . All of this information is sent to a review board , which will vote to decide if the Candidate should be accepted to Officer Candidate School . These review boards generally convene only once a month . After receiving a majority vote of acceptance from the review board , the Officer Candidate is officially accepted into the Officer Candidate Program and scheduled for a class . Training . OCS screens potential officers using a program designed to test and assess the candidates with an emphasis on confidence and leadership abilities . This includes evaluated events such as the leadership reaction course and small unit leader evaluation exercise . Regardless of course , the instructors usually include officers to handle most academic instruction , enlisted sergeant instructors ( Staff Noncommissioned Officer s taken from the drill instructor community ) to conduct most of the day - to - day management , and other instructors ( most often non - commissioned officer s ) to teach most field skills . Officer Candidates on both courses have many related expenses ( including travel to and from Officer Candidate School , meals , and lodging ) paid for them , and receive a stipend while in training to pay for uniforms , books , and other supplies . The Training and Education Command designs the program of instruction for OCS . Platoon Leaders Class . The Platoon Leaders Class normally consists of two six - week training sessions taken between consecutive school years , which occur in the summers with no commitment during the school year . Young men and women at any accredited four - year college or university are eligible for this class . Officer Candidates that attend the Platoon Leaders Class may opt for either the PLC Juniors / Seniors program or the PLC Combined program . In the Juniors / Seniors program , a freshman may attend the PLC Junior course the summer between their freshman and sophomore years , then attend the PLC Senior course the summer before his senior year begins . Sophomores can attend the PLC Junior course the summer before their junior year in school and the PLC Senior course the following summer . PLC Combined is a ten - week program for those interested in completing officer screening during a single summer after completing their junior year in college . Training includes academic and field topics . Academic subjects covered include Marine Corps history , leadership , close order drill , weapons handling , and general military subjects such as land navigation , the Uniform Code of Military Justice , interior guard , moral and ethical leadership , and basic combat . PLC candidates need to be physically fit as the physical training is demanding , for example , Officer Candidates in a PLC Senior course run and hike an average of or more during a six - week period . Those who opt for the Juniors / Seniors program will find that the divided program is tailored to provide progressive training . The Junior course is an introduction into the Marine Corps , and allows the candidates to be evaluated and motivated for a possible commission . Physical training , small unit leadership , and basic infantry tactics are addressed , as well as significant academic instruction . PLC Seniors is an advanced course of indoctrination and contains similar physical training , small unit leadership , infantry tactics , and academics ; but at a faster rate and with more instructor - induced stress . Those candidates who opt for the combined course cover the same areas of instruction , but it is integrated without the need to reevaluate candidates due to a year - long gap . NROTC midshipmen attend the PLC Seniors course for their final summer cruise , nicknamed " Bulldog " . Officer Candidates Course . The main alternative is the Officer Candidates Course , which is designed for college seniors or graduates and enlisted Marines , and consists of one ten - week training session . While the curriculum is identical to the 10 - week PLC Combined session , OCC is held three times a year ( winter , summer , and fall ) , and accepts only college graduates . Additionally , graduates of OCC are commissioned immediately upon graduation of OCS . The Quigley . The Quigley is a legendary water obstacle used in training at OCS . Lieutenant Colonel William J . Quigley , a veteran of both the Korean and Vietnam War s , designed it in 1967 . It consists of a long canal with cement culvert s submerged in swampy , snake infested water ; candidates must swim through the Quigley as a part of the OCS training program . Further training . Officer candidates who complete OCS ( and have obtained their college degrees ) are then commissioned as Second Lieutenant s and sent to The Basic School ( TBS ) at Quantico for six months of further training with other newly commissioned Marine officers from all other commissioning programs . At TBS , they receive the skills and knowledge necessary to lead Marines in combat ; much like " every Marine is a rifleman " , every officer is introduced to the skills necessary to lead a provisional rifle platoon .