This project concerns the design and construction supervision of the Art Gallery of the “Thessaloniki’s Fraternal Charitable Organization”. This particular project is located in the underground space of the Building and has a total surface of 170m2 of which 135m2 are occupied by the exhibition space. During the design process special attention was given on highlighting the stone masonry which not only shows the way the building’s foundation was laid but also provides references on the building’s history. The element of the composition that pops out as more characteristic and original is the contrast that the metal staircase – with the transparent treads and side parapets – brings out. This staircase was costume made and designed for this particular space. The floor is made out of a grey decorative cement that is the key element on which the Gallery is “based”, whereas the whitish walls with the use of special lighting seem to recede and create an illusion of depth.