This book examines the experience of Medellín, Colombia's second largest city, in seeking to reduce poverty and integrate large marginalised areas, marked by years of severe poverty and violence, into the urban fabric. It pays particular attention to the impact of two aerial cable-cars connecting high density hilly neighbourhoods with the rest of the city, and an associated urban upgrading programme. It also contrasts Medellín’s successful experience with that of Soacha, a municipality adjacent to Bogotá, Colombia’s capital city, where an aerial cable-car has been proposed as a means of linking two low-income hilly neighbourhoods with a main arterial road. The contrast between a well-resourced, well-managed municipality like Medellín with a dense and homogenously poor and institutionally weak municipality like Soacha offers valuable lessons to other cities in Latin America and elsewhere. Contributions draw from a two-year research project coordinated by the Development Planning Unit, University College London (UCL), in conjunction with Universidad Nacional de Colombia (Medellín campus) and Universidad de los Andes in Bogotá. In addition to the detailed case studies of Medellín and Soacha, the book also brings together cases in Latin America where aerial cable-cars have either been built or proposed in low-income neighbourhoods, including Caracas and Rio de Janeiro.