The Spanish Pavilion introduces a new term to the architectural lexicon: Internalities. This concept explores how architects can move beyond the environmental externalities associated with conventional architectural practices in order to decarbonise the construction sector. Within this framework, Internalities highlights how a new generation of Spanish architects is developing compelling proposals rooted in local ecosystems of territorial production. These ecosystems aim to minimise dependence on interconti- nental resource transportation, fostering an internal balance between ecologies and economies. The exhibition is organised around five axes of internalisation that are crucial to the decarbonisation effort: Materials, Energies, Labor, Residues, and Emissions. Each axis is developed by a team of architect-researchers and a photographer, focussing on a specific region of Spain. The exhibition thus spans Northern Spain, Galicia, Madrid, Catalonia, and the Balearic Islands. By examining these regions, the exhibition shows how to move away from hegemonic models of architectural construction. It questions in what ways, to what extent, at what cost, and through which buildings, cities, and territories Spanish architecture is shifting away from economies of externalisation.