Located in one of the lots of the former Expo 1992 in Seville, a tertiary landscape saturated with high-flownsingularities, a heritage from the exhibition´s pavilions, the project includes areas for certain medical specialties the surface of which is proportional to the capital invested in each of them. From this proportionality, we proposed a section shaped as a bar chart, setting up three linked voids forming a large space that develops the Center´s circulation and activities. A compact piece raises, rough and opaque to the outside world and dug in it, using the void and porosity as the fundamental work subject. The architecture becomes what is in the middle, between what is built, embodying the Debussy´s quote: “Music is the space between the notes”. The void is formalized through the combination of different floor plans with a similar porosity but distributed in different ways, creating patios, terraces and voids. The circulations run parallel to the void, one side for the patients and the other for the medical staff, so that both meet only on the trays that conforms each specialty and that floats over the interior void.