Speaking and to deepen on the theme of the public library in Latin America is done difficult to do it if themselves does not keep in mind the realities, tendencies and perspectives that this new century implies, as a result of the deep economic, political, social, cultural, educational, technological and informative changes that have lived themselves, especially in the last two decades, and in which undoubtedly they will come. It is because of it that, the present text undertakes, since what has been called "society of the information", "informational society", "society of the knowledge" and other terminological forms to be referred to a same transformation, the challenges (opportunities and threats) that has implied, is implying and will imply for the conception and operation of the public library, to leave also, of the different forms to live, to assume or "to survive" to this new society according to each context, well be, in a determined country, region, city, rural zone or sector. For that reason it splits of the conception of the public library as democratic institution, related to the guarantee and development of the right to the information, to the education, to the recreation and to the culture; their to drive this narrowly related to the freedom of speech, base of the democratic contact; its function is founded in the formation of citizens that have random access and free to the information, independent of the backups and formats in which be found. Since these considerations themselves structure the book, which have been elaborated, since the contribute of diverse theoreticians in the theme, since the experience developed in the academy and of the processes of investigation developed by the research team in Public Library; and since the practical librarian; with the only pretension to serve of material that contribute to the processes of formation of the people that lend its services in the public library. The contents are structured in three chapters. The first one corresponds to the framework contextual of the public library, concretely the above-mentioned thing with the company of the information and in the society of the knowledge; chapter that develops since the search of the answers to the ten large challenges that are presented him to the public library in Latin America, as one of the main institutions that participates in the information transfer network or as traditionally itself identifying, the information transfer cycle. After defining these challenges or better than establishing the role and place of the public library in the region, the normative, historic, and conceptual framework be planted of the this institution, which does part of the second chapter and in it they are undertaken the main referring conceptual, historic and normative-legislative that have been given in the Latin-American environment. To finalize, the material develops in a way more extensive the chapter three, which corresponds to the organizing framework-administrative-strategic of the public library, this chapter realizes the strategic planning in light of the functions of the public library, of the evaluation and indicators of measurement, and of the three axes constituents of the library: Users, Collections and Services; complemented with concepts and tools originating in the management and the marketing.