Madrid Book Fair has been held since 1933 and is one of the main cultural events in the capital. The proposal is based on transparency and luminosity as its leitmotiv. A system was sought that would allow a quick assembly (the construction was carried out in 15 days) consisting of translucent cellular polycarbonate panels and Viroc on a metal structure. The uniqueness of the Pavilion compared to the rest of the fair is emphasised by a specific atmosphere of seclusion within a bustling environment (around 400,000 visitors in 2021).