What happens in Vegas, stays in Vegas

"What happens on tour, stays on tour" is a notorious phrase or saying agreed to by men who get together and travel either interstate or overseas for sporting tours. In essence, the phrase means that all exploits during the tour must be kept strictly confidential, never to be discussed with anyone outside the group. In more recent years, the phrase has also been applied to men attending music gigs, going on business trips and fishing holidays. The term is commonly used in the United Kingdom, Ireland, Australia, New Zealand, South Africa, Canada and the United States and is also known as "what goes on tour stays on tour","what happens on the road stays on the road", and, among members of the United States military, speaking of temporary duty assignment, "what happens TDY stays TDY".

The phrase has been described by Samantha Brett, a writer for The Age, as an "unspoken male pact that for centuries can never be broken". In essence, if you were there you may discuss the events, but if you were not there, you get nothing. In contrast, Rugby for Dummies describes the phrase as meaning that particularly funny, embarrassing, or debauched moments are for consumption only by the tourists themselves and not casual listeners back home.

It is believed that the phrase originated in 1970 during an overseas rugby union trip, and quickly cascaded into many other sporting codes such as cricket and football. The phrase has subsequently evolved into a "code of honour" amongst those males participating in the trip or tour. Many groups or teams travelling interstate or overseas have adopted the phrase, that mainly relates to sexual conquests and binge drinking. However, the phrase can also relate to other forms of unacceptable behaviour and etiquette.

It has been stated that there are two rules embedded in the code. Firstly, it must be a group of males in team environment, travelling away from home, where they are unconstrained from the usual forms of acceptable behaviour. The second rule is that all exploits must be kept strictly confidential, never to be discussed with anyone outside the group, particularly wives and girlfriends (also known as WAGs). Research showed that the men in sporting teams spent most of their time either thinking about, or engaging in recreational activities.

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Wikipedia