Mess dress is the military term for the formal evening dress worn by military officers in the mess or at other formal occasions. It is also known as mess uniform and mess kit. It frequently consists of a mess jacket and trousers worn with a formal shirt and other formal accessories, though the exact form varies depending on the uniform regulations for each service.This style of military dress is largely restricted to the British, Commonwealth of Nations and United States armed forces, though it is also sometimes worn by members of civilian uniformed services and members of a Royal Household. The French, Imperial German, and other navies adopted their own versions of mess dress during the late nineteenth century, influenced by the Royal Navy. While predominantly a uniform worn by commissioned officers for whom it is mandatory, it may also be worn as an optional uniform by senior enlisted personnel in the U.S. Navy and U.S. Air Force, and by non-commissioned officers in the British Army and Royal Air Force.