A broken trendline is a technical signal that can suggest a change in trend is at hand. If low volume (rather than high volume) accompanies the break of a trendline, the signal is not as strong or convincing. It can make sense to wait a day or two to make sure that the trendline break is legitimate. Once a position is opened, risk management—in the form of stop-loss orders or trailing stops—can help protect profits after a trendline break.