This updated and expanded new edition continues the theme of the first edition of emphasizing the substantial growth of street gangs throughout the world. Although a substantial amount of research on street gangs has been conducted in recent decades, much of it has focused on the United States. This book summarizes much of the research being conducted in many other countries where the street gang phenomenon is currently developing, which includes poverty, the retreat of the state, increasing income inequality, urbanization, population growth, exploitation, marginalization, underground economie.