The D’Alembert is one of the most secure systems available, since after a loss, you may only double your bets rather than doubling them each time. This is an equal-risk betting system.

All you have to do with this system is choose a starting bet, then add one more after a loss and decrease one by the same amount after a win. The idea is that once you’ve accumulated as many losses as wins, your account will be in the black by the quantity of bets you’ve made.