Moral rebels: those who speak up and speak out against bad behavior, be that to tell a bully to cut it out, to confront a friend who uses a racist slur, to report a colleague who engages in corporate fraud. Moral rebels tend to have character traits like feeling confident in themselves and less socially inhibited; they don't feel a need to conform. Research in neuroscience reveals that people's ability to stand up to social influence is reflected in anatomical differences in the brain. But beyond personality and grey matter, moral rebels have seen moral courage in action. They also tend to have greater experience with people of different background and higher levels of empathy. Although moral rebels show specific traits, the good news is, anyone can learn to be a moral rebel, and the world needs more of them right now.