The Labouchére System, also known as the Cancellation or split Martingale System, is a well-known mathematical strategy with which to play roulette. Players who bet according to this strategy determine the desired profit amount before they start playing. They also make a list of positive numbers in advance that add up to the particular profit amount. These numbers can be completely random or can be in a series, such as multiples, or only odd numbers, etc.
How Does the Labouchére System work?
Each bet amount consists of the sum of the first and last number on the list. If this bet results in a win, then these outer numbers will be removed from the list, and your next bet is the sum of the two new outer numbers. If the bet results in a loss, the bet amount is added to the end of the list, and thus part of the sum of the next bet amount. This process is repeated until the list is fully crossed out, and the desired amount is won, or the budget is through.
Keep in mind that the Labouchere system is intended to be applied to Even/Odd, Red/Black, or 1 – 18/19 – 36 bets only.

Example
If you wish to win £ 25, and you have chosen the series 2, 5, 3, 9, and 6 (sum = 25), then your first bet will be (2+6=) £ 8 on red or black. If you win, then you cross off the two outer numbers, 2 and 6. Your next bet would be the two new outer numbers, (5 + 9=) £ 14 on red op black. Should you lose this bet, then 14 is added to your list, which now looks like this: 2, 5, 3, 9, 6, 14. Your next bet on red or black would thus be (5+14=) £ 19. If you win this bet, 5 and 19 are crossed off the list, so your next bet is (3+9=) £ 12. Your list now looks like this: 2, 5, 3, 9, 6, 14. Should you also win this bet, then you have completed the game.
You have thus bet, in total £ 53, but have won £ 78, which means that you won exactly £ 25.
Does the Labouchére System really work?
Since we are betting on low-risk bets, the bet is always lost when the ball falls on 0 or 00. Since the odds are not entirely 50/50 on the roulette wheel, this might lead to more losses than expected. The clearest disadvantage of this system is thus your available bankroll. If the list gets too long, then your bets also increase rapidly, leading to higher wins, but also losses. The casino’s betting limits also might limit your playing range, so try this on a table with very high betting limits.

This system does, however, provide not only structure, and improves your chances, but it also manages your losses better, since you always end on a win. Not only does this system work extremely well, but it also keeps you on your toes, since you’re performing quite a bit of maths while betting simultaneously.
Splitting the Bets
When your betting amounts in the series become too high for your bankroll, you could try to split the series, to reduce your losses. By playing through the lower half of the full series, your bankroll will again be increased for the second half of the series. This way, you can still win your total desired money back, without having your bankroll go into the thousands!