The purpose of this chapter is to provide readers with an insight into gang-related violence, and responses to gang-related violence, across a number of European cities. To this end, it brings together city-specific sections written by subject experts who have resided and conducted research in four European countries: the UK, Belgium, Russia and Sweden. Each sub-section of the chapter follows a similar structure: first, we provide contextual information about gangs in each city; second, we discuss data on gang member demographics; third, we consider the nature and scale of gang-related urban violence; and fourth, we outline some of the main policy responses aimed at tackling gang violence, including any references to public health approaches to violence reduction.