Gangs have both worried and fascinated Americans for many years, but gangs are not a uniquely American problem; they can be found all over the world, from Sweden to Japan. Most of what people learn about gangs through movies and television does not reflect the reality researchers have discovered through firsthand studies of gang life. The detailed main text, informative charts, annotated quotes from experts, and full-color photographs explore this reality and various social factors that allow gangs to arise. With this knowledge, young adults can identify areas where they can make a difference in their own communities.