The minimum age varies by service. To become an officer one must have a college degree or go through OCS. For service academies, like the U.S. Naval Academy, enrollees must be between the ages of 17 and 22. Reserve Officer Training Corps (ROTC) enrollees must be between the ages ofl7 and 21. Officer Candidate School (OCS) enrollees are between the ages ofl9 and 29. The National Guard may choose to enroll soldiers in the OCS program up to age 35.
Officers usually begin their careers by gaining experience in a chosen occupational field. They are generally college graduates. They also complete basic physical training while completing their education or afterward (varies by service).
Officers can progress through 10 pay grades. Individual performance is compared with the performance of all other officers in similar pay grades. A selection board reviews every aspect of each officer's career performance to select those best qualified for promotion. Factors for promotion include:
- Career-long performance of job duties, leadership, and management
- The pursuit of, and success in, positions of increasing responsibility
- Successful completion of required qualifications and professional military education
- Appearance and behavior