The United Nations Environmental Council (UNEC) will be the sixth UN Council and will deal with all the global issues concerning sustainability, searching at the same time all the political, economical and technological information that can be connected with sustainability development. It will be a central organization that consists of four entities: collect, produce, propagate and exchange information on sustainability worldwide. These four entities included in the design as well as its global importance make us realize its icon status worldwide. Its existence and appearance should persuade people that sustainable design and behavior towards the environment can improve our way of living. Architecture is integrally connected to social and economical issues that undoubtedly should be considered during the process of designing. The question is how to express sustainability in the design of a building so as to be understandable by everyone, even to those who wouldn't have the chance to visit that building and only see it on pictures? Should it be clearly expressed at the facades and the outer skin of the building or should it be integrated in the climate and structural design of the building? Starting with the research on the site it seems necessary the intervention on it so as to improve its urban quality, its relation with the existing built environment and the natural elements, like water and the green space. At the urban scale principles, the green space of the existing green park should remain in order to enhance the sustainability principle of the project. As far as it concerns the building, several facts will affect the design. It is a building which addresses to five different users: the delegates, secretariats, businessmen, researchers and the regular civilians. However apart from the users it will be a representational building which should be recognizable from people that either visit it or see it at pictures. My intention is to design a building that would be easily recognizable from the public and at the same time be friendly and open to those who have the chance to either visit it or even work there. The proper use of the materials and the structure will help me to find the right balance of the scale that these two principles (easily recognizable and friendly) have.