Amazon Italia's new Business Centre, designed by GBPA Architects, is a pragmatic example of architectural and plant retrofitting that harmonizes functionality, aesthetics, and sustainability. A new life project that preserves the historical identity of the former Tecnimont office building, built between 1970 and 1975, designed by Claudio Longo and Giulio Ricci.     The replacement of the external envelope was thus intended as a reference to the pre-existing project, which had made the building a landmark. It was made of prefabricated self-supporting curtain walls in anodized aluminium and glass, with vertical aluminium sunshades.      The new interpretation has adopted the same cohesive formal approach, with all-glass curtainwalls, including vertical sunshade elements, which pay homage to the original design with a total dematerialization of the fronts.  The strong constructive collaboration between GBPA and TENKE, between architectural and technical design respectively, has made it possible to develop a new concept of the building, with a profound rethinking of spaces, distributions, and systems.     With a gross floor area of 40,000 m2 and over 20,000 m2 of office space, the headquarters consists of two parallel linear slats (block 1 on Viale Montegrappa, block 2 on Bastioni di Porta Nuova) with a central connecting body. The demolition of the third block on Viale Melchiorre Gioia has opened space for a large internal access square, covered by a new glass canopy of about 500 m2. The solutions for the interiors are aimed at maximizing the flexibility and functionality of the building, providing partitions and modulations of the interior spaces for various layouts (half-storey, full floor, several adjacent or contiguous floors), anticipating a future division between tenants and autonomous management of the systems. This approach had the multiple advantage of increasing the interest of the intervention on the real estate market and of obviating the numerous constraints that the existing structures entailed, consisting of regular spans of 4.80 m in all the work environments. The identification of a flexible planning mesh will make it possible to make the most of all the interior spaces, allowing it to be easily and quickly reconfigured over time.     The configuration of the central volume, raised to the same height as the other two wings, offers an independent horizontal connection at all levels, maximizing the usability of the spaces and partitions. The systems are designed to ensure maximum energy efficiency and reduce operating costs. The energy cycle is designed to limit the impact on the environment, with a cultural approach sensitive to the reduction of consumption and maintenance costs, also through the use of renewable or low-impact sources. In addition to the new and high-performance external envelope, in fact, a mixed system was opted for with a condensing heat pump with cold groundwater (meeting most of the needs) and air (for the remaining part).      The careful design choices have made it possible to achieve the LEED Shell & Core Level Platinum environmental certification. In its essence, the design approach has paid homage to the historical iconicity of the original building, tracing its old forms, but has projected its soul to a more contemporary functionality, adapting it to current regulations, both at the plant and structural level, and in terms of fire prevention and healthiness of the spaces, without distorting its original conception.