The library system of Moscow stands today as a piece of a wider infrastructure that no longer exists. The 448 libraries within the city’s boundaries belong to the list of soviet welfare infrastructures, along with hospitals, schools, clubs and sport centres, a complex social machine of which they are a fragment. Their present connotation, distribution, and function largely depends on this past, although the history of the libraries stretches beyond and before the 75 years of soviet regime. Its architecture can be seen as an element of continuity in Moscow’s XX century history, having survived through the change of three different regimes over one century. This continuity is expressed in their physical presence of the city, in their interiors, their collections, and especially in their direct link to political power; under each regime the libraries expressed the political message of the time. The present condition of the libraries, in this perspective, is that of a large system in transition where the lack of political and economical interests have slowed the changes that affected other institutions. The libraries constitute a huge resource of public space -their rooms alone would cover 25 hectares, an area three times that of the red square. This monumentality, however is expressed in a long list of small interiors, worn out collections and minor histories. Recognizing the library system as a whole, before considering its circumstantial situations, is a way to understand how the network was designed and maintained. The system embodies principles of soviet urbanism; libraries were related to the number of inhabitants and geographical distance from other services, they occupy the ground floors of the buildings and are evenly spread throughout the city. This quantitative approach in the planning faces today a variety of issues; bringing back the libraries to their present condition, studying their contexts and seeing which of these relations still exist, which don’t and which could be formed gives directions on how the network could be reorganized and on what it could accomplish. Such connections are often hidden behind a curtain of low fences, rows of garages, and blurred by the different management systems of the city’s grounds. The Atlas proposes three ecologies and a series of public elements to which the rooms can relate both on the scale of architecture and of management. Establishing a common language among the diversity of circumstances and building an atlas of relations between the libraries and their contexts is a first step towards the new cycle of the system and in recognizing the new geography of the libraries.