Martingale principle is popular in FX trading; its works very well if you have a high provability system. High probability means more the 70% winning ratios in trading. my trading strategies are able to produce 70% winning rates in any given time frame ,I was following Martingale principle. Any fundamental news related trading will consider only 50% winning ratios. Yesterday I lost three consecutive trades, though USD/JPY was up 200 dollars, I was not active enough to put it in a break even trade. After three losing trades I was sure that my system will produce a winning trade and I just follow the principle. Here is one problem if you don’t know what’s your system probability is, you shouldn’t be using this principle.