The building Castellana 81 won the prize for Best Renovation 2017 awarded by AEO, the Spanish Association for professionals, companies and institutions working in Corporate Property Management. Some of the aspects of the building that have secured it this award include its efficient transformation through the renovation of its functional flexibility and comfort parameters. For the AEO, the technical efforts, professionalism and the end result of this full refurbishment serves as an example of how to conserve, recover and update singular buildings that adapt to current and future user needs, quality standards and introduction of installations, technologies, finishes and sustainability criteria aligned with today’s needs.