An emerging trend is listening to angry customers to get insight into prioritizing product development investments. Listening to happy, loyal customers is important, but they can’t teach you everything you need to know. You learn more from talking with angry customers. Instead of the common reaction of handling, calming, and appeasing angry customers, some companies are learning how to listen to their screamers and profiting from it. They are proving they were listening by taking action and fixing things that matter to customers. In this talk I discuss the history of this trend, show how three big companies are adopting this technique, and give a case study of using this technique with a client.