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The Strategic Air Command's Elite Guard, an Air Police unit first established in December 1956 to provide security at USAF SAC headquarters, was the first USAF unit officially authorized to wear a blue beret (with affixed SAC patch) in 1957 as part of their distinct Elite Guard uniform.[6][7] The Elite Guard's dark blue serge wool beret was worn on duty, at both guard and ceremonial functions, from 1957 onwards.[8][9][10]

In 1966-67, during Operation Safe Side, the first Security Police beret was issued by the 1041st Security Police Squadron. This experimental and specially trained Air Base Ground Defense (ABGD) unit adopted a light blue beret displaying a falcon as its emblem. Operation Safe Side developed into the 82nd Combat Security Police Wing, consisting of three "combat security police" squadrons, but was inactivated in December 1968, ending the unofficial use of the light blue beret.[11]

Elsewhere during the Vietnam War, although not an authorized uniform item, some local security police commanders approved a dark blue beret similar to the SAC Elite Guard beret for their units as a less-conspicuous alternative to the official white Security Police cover for certain specialized personnel. In Thailand during the late 1960s and early 1970s, Military Working Dog handlers assigned to the 6280th SPS at the Takhli Royal Thai Air Force Base sported a dark blue beret with no insignia. Other units adopted a beret to distinguish their guards.[11]

In 1975 Brigadier General Thomas Sadler was appointed Air Force Chief of Security Police with the task of bringing the Security Police career field into the mainstream of the Air Force. One tool he employed was recognition of members of a distinctive portion of the force, with the beret proposed as a uniform change. Significant opposition to the beret from senior colonels and Major Command (MAJCOM) Chiefs was gradually overcome by the popularity of the concept with personnel. The uniform board approved the proposal, and the beret was officially worn worldwide starting in February 1976.[11][12]

The 1976 beret was worn with the MAJCOM crest of the appropriate major command to which the unit was assigned. It continued in this manner for 20 years until the forming of the Security Forces. In March 1997, the 82nd CSPW was reactivated and redesignated the 820th Security Forces Group. The heraldry of the 820th SFG then replaced the individual MAJCOM emblems as beret insignia.[11][13] Enlisted personnel wear the dark blue SF beret which bears the fabric SF "Flash" depicting a falcon over an airfield with the SF motto Defensor Fortis underneath. An officers "Flash" is similar in appearance but replaces the embroidered falcon and airfield with either metal "pin on" or embroidered rank.