Architecture is a system, physical elements related to each other by strong and clear rules. This is an abstract exploration of density, by studying how diverse and heterogeneous spaces and functions usually coexist in close relationship, altering their character and enriching the intermediate or transition spaces. This publication compiles some of the work produced at the Architecture Design Studio 'Densities', instructed by Rubén Alcolea and Sam Ghantous at AAP Architecture Art and Planning, Cornell University.