While cities have long been associated with employment, development and economic growth, hundreds of millions of children in the world's urban areas are growing up amid scarcity and deprivation. This publication presents the hardships these children face as violations of their rights, as well as impediments to fulfilling the Millennium Development Goals. It examines major phenomena shaping the lives of children in urban settings, including migration, economic shocks and acute disaster risk. It also provides examples of efforts to improve the urban realities that children confront and identifies broad policy actions that should be included in any strategy to reach excluded children and foster equity in urban settings driven by disparity.