The number of roulette system strategies and systems on the market is staggering. You can buy books, eBooks, PDF files, and even audio CDs and podcasts that claim to teach you betting systems that can’t lose. Save your money.

Most roulette systems make you think that you’re shrinking the house’s edge or giving yourself an advantage over the rules of roulette. But gaining an advantage in roulette is impossible. The best you can do is avoid the worst bet, which is the “five numbers” bet on an American roulette table. You can cut the house edge by 50% or more by sticking with European roulette games if you can find them.

No roulette strategy or system works. This page looks at some common roulette betting systems and why they won’t help you win.

The Martingale System is the most common roulette betting system, but it’s as useless as any other roulette betting system. A Martingale player doubles her bet after each loss, so that if she wins, she’ll recoup her previous loss along with an additional betting unit. If you lose twice in a row, you double the amount of the second bet, and so on. Each progression is supposed to end with you being one unit ahead. Variations exist, but they’re just a more complicated way of eventually losing your roulette bankroll.

If you don’t think too hard about it, doubling your losing bets and pocketing your winnings makes sense. A passing glance might even be enough to convince you to try it yourself. But maximum bet sizes and the limits of your own bankroll make the Martingale System useless.

Here’s why:

If you’re playing a roulette game with a $5 minimum and a $500 maximum bet and you use the Martingale System, you’d be extremely limited in the number of doubled bets you can make. Your first bet would be $5, then a loss would force you to bet $10, another loss would require a $20 bet, then $40, $80, $160, and $320. That’s only seven bets, but now you can’t continue with your system because of the table limits.

Some proponents of the Martingale System insist that 7 or 8 losses in a row is rare. They’re right, but only to an extent. The Martingale guarantees a few small wins, but eventually it also guarantees a huge losing session. In the example above, by the time you’ve made 7 bets, you’ve lost $635…chasing a $5 net win.

The d'Alembert System has the benefit of a cool name. Sometimes that’s all it takes to convince people that something is legitimate. Roulette is a French word and so is d’Alembert. It must work, right?

Like most other roulette systems, the d’Alembert System doesn’t work because it assumes that winning one bet has any impact on future bets. The d’Alembert System teaches players to remove a single chip from your bet after every time you win. For losing bets, you add a single chip instead of removing one. It’s similar to the Martingale System, but with a different system for adjusting your wagering amounts.

Roulette wheels are not alive. They have no idea what’s happening in a game of roulette, and they don’t remember whether or not you just won or lost. Each spin of the roulette ball is independent of each other spin. Altering your bets based on wins and losses makes no mathematical sense. Each spin has the same odds as the one before and the one after. Every roulette bet has two possible outcomes—a win or a loss. The odds of each are built into the game, and changing the amount you bet doesn’t change those odds. What happened on previous bets doesn’t change those odds either.

Ian Fleming described the James Bond roulette system in the 1960s as the only way to turn $10 into the “the price of a good dinner.” Sometimes called the Labouchere System (another French-sounding roulette system) this method also suggests you increase your bets after losses. Here’s how it works:

First, you buy as many chips of the minimum bet as you can afford. Then you write the numbers 1 to 5 down on a piece of paper. Your first bet is the sum of the top and bottom numbers: 1 + 5 which equals 6. Place a bet with 6 of the minimum bet size chips. A win means crossing out the top and bottom numbers, then betting the sum of the new top and bottom digits. A losing bet in the Bond system means writing the amount of your loss at the bottom of the number column. You then bet the total of the top and bottom numbers again, 7 in our case. An increased bet on a loss is susceptible to all the same problems as the betting strategies described above, and will not work over time.