Infrastructure can be wielded as a means of promoting the common good or as an institutional weapon of exploitation. While the highways, bridges and dams funded by international economic interests and built in outlying regions like the Amazon play a role that is difficult to conceive of as being anything other than devastatingly exploitative, the public parks and greenways of the world’s major cities also clearly serve economic functions while delivering a variety of benefits to the common good. Infrastructure can be conceived of as opportunistic and multilayered, serving explicit functions of enabling mobility, energy, and communications – but also potentially prioritising access to light, air, and water: creating open space for social gathering and spatial continuity for ecological habitats. This is true whether infrastructure is regarded as a public space or as private commodity. Semi-public spaces now proliferate in major cities. Of course, the term ‘semi-public space’ is effectively a euphemism for ‘private property’, and while this trend might be criticised, there are also examples of these spaces being used in such a way as to provide alternative commons when the public are denied their right of free access to public space.