Building on Lefebvre's claim of a complete urbanisation of society, Neil Brenner and Christian Schmid argued from around 2011 that urbanisation has become a planetary process that can no longer be confined to dense settlements. They distinguished concentrated urbanisation in cities from extended urbanisation across hinterlands, supply zones, oceans and even wilderness drawn into urban metabolism. On this view the rural-urban divide dissolves, as remote landscapes are operationalised to sustain urban life. The thesis called for new categories beyond the bounded city.
It challenged the very category of the city, prompting analysis of how urbanisation reorganises the whole planet, from mines to logistics corridors. Planetary urbanisation reframed urban studies around processes that extend far beyond the built-up area.