This chapter provides an overview of the police militarization phenomenon. It establishes some conceptual precision before examining the empirical evidence documenting the police militarization trend. The chapter distinguishes between indications that are necessary in applying the PPU label and those which would only contribute to labeling the units and their activities as paramilitaristic. It focuses on quality of life issues like illegal parking, loud music, bums and troubles. Militarization's companion concept, militarism, is an ideology focused on the best means to solve problems. It is a cultural set of beliefs, values, and assumptions that stress the use of force and threat of violence as the most appropriate and efficacious means to solve problems. It emphasizes the exercise of military power, hardware, organization, operations, and technology as its primary problem-solving tools. A controversial police killing of an unarmed African-American man by a white police officer in Ferguson Missouri sparked massive civil protests, within Ferguson and other US cities.