All that is required for evil to flourish is for good folk to do nothing. When society fails--when corruption or hatred or apathy take root--the helpless and the marginalized suffer first. And all too often heroes must rise from the ranks of the dispossessed, not to impose their will on others, but to provide the same safety and justice so many others take for granted. The Vigilante's Handbook is a sourcebook of street-level action and adventure for your Mutants & Masterminds campaign. This book provides everything you need to stand up and push back against the overwhelming corruption and inequality that threatens so many, often without the deep pockets or impressive powers the four-color heroes rely on. This sourcebook features guidelines for creating street-level vigilantes, from low-powered brawlers to high-powered but maligned heroes who work from the shadows, and optional rules for overwhelming enemies with your menacing presence or fearsome reputation and for gauging and tracking your hero's reputation. Vigilante's Handbook also looks at what kinds of predators prowl the urban jungle, from corrupt cops and politicians to criminal masterminds and assassins, and introduces a flexible template system, separating your villains' role from their powers. The world of Earth-Prime is also expanded with a gazetteer of Ferroburg, a city of corruption and struggle in desperate need of heroes. Welcome to a world where your compassion, your human decency, and your ability to take a punch mean more than your satellite headquarters and fancy costumes. Welcome to the streets.