This work addresses the public library, its significance, importance and challenges in contemporary social, tries to clarify, albeit briefly, the emergence of public libraries and concepts used for this term, which will support its operations and building policies. Which discusses the social importance of the public library in the twenty-first century, and how their performance has become critical as a space for dialogue and citizenship, as well as set up a center of cultural promotion, in that it gathers and articulates the various manifestations artistic and cultic. Highlights the main challenges that public libraries face today, or in the elaboration of public policies for the book and reading, either in funding through alternative funding mechanisms, in order to make viable their actions. At the end, describes the performance of the Superintendent of Public Libraries as manager of the Biblioteca Pública Estadual Luiz de Bessa, considered the largest library in the state, and also the actions of the Sistema Estadual de Bibliotecas Públicas Municipais, which has a network of 839 libraries, distributed 801 municipalities of Minas Gerais.
Public library; Social role; Political action