This article is about headgear. For information about the special forces see Green Berets.

The green beret is the official headgear of the Royal Marine Commandos and the United States Army Special Forces (Green Berets). Both special forces wear it because of a shared tradition which goes back to the British Commandos of World War II. Although it is unusual for American units to wear distinctive head gear, it is the norm in the British Army, where most regiments wear hats or cap badges which reflect regimental battle honours and traditions.

United States Army Special Forces, the Green Berets

In the U.S. armed forces, the green beret may only be worn by personnel awarded the Special Forces tab, signifying that they have been qualified as Special Forces (SF) soldiers.

The U.S. Army Special Forces wear the green beret because of their links to the British Commandos of World War II. The First Ranger Battalion, commonly known as Darby's Rangers, was formed in Northern Ireland during the summer of 1942. On completion of training at the Commando Training Depot at Achnacarry Castle in Scotland, those Rangers had the right to wear the British Commando green beret, but the U.S. Army disallowed this, and Rangers never officially wore their berets.

When visiting the Special Forces at Fort Bragg on October 12, 1961, President Kennedy asked Brigadier General William P. Yarborough to make sure that the men under his command wore green berets for the visit. Later that day, Kennedy sent a memorandum which included the line: "I am sure that the green beret will be a mark of distinction in the trying times ahead". On April 11, 1962 in a White House memorandum to the United States Army, Kennedy reiterated his view "[the green beret is] a symbol of excellence, a badge of courage, a mark of distinction in the fight for freedom."

The Royal Marines (British)

Once a Royal Marine has passed the Commando Course, he is entitled to wear the green beret and the 'Royal Marines Commando' flash on his uniform.