The Martingale strategy is a high-risk money management technique in forex trading. It involves increasing the size of a trade after a loss, with the aim of recouping previous losses and making a profit. However, this strategy can quickly lead to significant losses if the market moves against the trader, as the size of the trades continues to increase. Traders who use this strategy must have a high risk tolerance and be prepared to accept the potential for significant losses. It's generally recommended that traders avoid using the Martingale strategy and instead use more conservative risk management techniques.