Vale Tudo or vale-tudo (Portuguese pronunciation: [ˈvali ˈtudu]; English: Everything Goes/Everything Allowed), also known as No Holds Barred (NHB) in the United States, is an unarmed, full-contact fighting style or competition format characterized by having very few rules. It became popular in Brazil during the 20th century and would eventually evolve into modern mixed martial arts (MMA). For years, "Vale Tudo" was used as a synonym for MMA in Brazil, but the term fell into disuse due to the emergence of stricter rules and the influence of the media to have a more "civilized" name. It is now used to refer to an early, more rules-free stage of the modern sport.
Vale Tudo initially started as an informal ruleset for fighters from different martial arts to fight each other. The Gracie family was known to organize their famous "Gracie Challenge", in which they would fight other martial artists in Vale Tudo bouts to prove the efficiency and superiority of their own Gracie jiu-jitsu. Many fighters eventually started to train specifically for Vale Tudo events, mixing striking and grappling, eventually advertising "Vale Tudo" as its own standalone style. For example, Marco Ruas referred to his hybrid style of Luta Livre and Muay Thai striking simply as "Vale Tudo".