Social movements are stronger when they sing. That's a lesson that has been amply demonstrated throughout history, and it's one that I have learned personally in working to develop trainings for activists over the past decade and a half. In Momentum, a training program that I co-founded and that many other trainers and organizers have built over the last seven years, song culture is not something we included at the start. And yet, it has since become so indispensable that the trainers I know would never imagine doing without it again. We developed a session within Momentum devoted to reviving song culture. We named it "Why did we stop singing?" This module teaches how to bring more music to our movements by breaking down common barriers like self-consciousness, discomfort with vulnerability, and lack of a shared repertoire. Once Momentum began incorporating it into its curriculum, "Why did we stop singing?" quickly became one of the most popular parts of the training. Over several years, many of the organization's trainers and leaders worked to develop the module and, as they did, some important lessons emerged. Chief among them: Music is a powerful tool that we have too often neglected in our organizing"and members of our movements are hungry to bring it back. The training was designed to promote a more sustainable culture of direct action, as well as to put traditions of mass protest in dialogue with longer-term models of structure-based organizing.