In the latter, the mayor took a progressive stance to locate high quality transport and cultural amenities in the poorest neighbourhoods. Consequently, new urban policies are needed to harness the benefits that arise from different groups of people living in close proximity to one another, rather than letting these heterogeneous urban conditions combust into intolerance, xenophobia and widening inequalities. In other words, the heterogeneity, density and diversity of cities, which is what makes them nodes of economic innovation and democratic progress, must be managed and planned, short of which these very variables that make successful cities can transform them into places of social exclusion and inequality.