Then, following a win, the player will bet two units. The player will continue “flat betting” in this way, never varying the amount bet, until the wager wins. If the wager loses, one unit will be bet again. To begin the progression, a single unit is wagered on an even money outcome, such as betting on Black at the roulette table. The object of the Paroli betting system is to obtain three consecutive wins in a row, while doubling the wager with each win.

Today, the Paroli betting system is most effective in wagering on roulette and baccarat, although it can be used for any game featuring even odds bets, including craps, Sic Bo, Pai Gow poker and, with some modifications, even blackjack. This tactic has been employed with some success since the 16 th century, when it was commonly applied to an Italian card game known as Basset. Its name derives from the Latin term, par, meaning “one that is equal.” In its simplest form, the system can be thought of as doubling a wager after each win until three consecutive wins are achieved. Paroli is a form of positive betting progression.