The process of allocating resources is conducted by determining a military budget, which is administered by a military finance organisation within the military. Military procurement is then authorised to purchase or contract provision of goods and services to the military, whether in peacetime at a permanent base, or in a combat zone from local population.
Each service has a uniformed head who is considered the highest-ranking officer within their respective service, with the exception of the chairman and vice chairman of the Joint Chiefs of Staff, and the chief of the National Guard Bureau. They are responsible for ensuring personnel readiness, policy, planning and training and equipping their respective military services for the combatant commanders to utilize. They also serve as senior military advisors to the President, the Secretary of Defense, their respective service secretaries, as well as other councils they may be called to serve on. They are as follows:
Because most of the concepts and methods used by the military, and many of its systems are not found in commercial branches, much of the material is researched, designed, developed, and offered for inclusion in arsenals by military science organisations within the overall structure of the military. Military scientists are therefore found to interact with all Arms and Services of the armed forces, and at all levels of the military hierarchy of command.
Examinees also receive a score on what is called the Armed Forces Qualification Test (AFQT). AFQT scores are computed using the Standard Scores from four ASVAB subtests: Arithmetic Reasoning (AR), Mathematics Knowledge (MK), Paragraph Comprehension (PC), and Word Knowledge (WK). AFQT scores are reported as percentiles between 1-99. An AFQT percentile score indicates the percentage of examinees in a reference group that scored at or below that particular score. For current AFQT scores, the reference group is a sample of 18 to 23 year old youth who took the ASVAB as part of a national norming study conducted in 1997. Thus, an AFQT score of 90 indicates that the examinee scored as well as or better than 90% of the nationally-representative sample of 18 to 23 year old youth. An AFQT score of 50 indicates that the examinee scored as well as or better than 50% of the nationally-representative sample.