This article approaches the decreases in illiteracy rates in Latin America indicating that, even in the countries where such rates are lower, the adult population without complete education still represents a very high percentage. It also exposes some conclusions of the research sponsored by UNESCO/OREALC, that focused on the literacy of adult populations in the capital or main cities of Argentina, Brazil, Colombia, Chile, Mexico, Paraguay and Venezuela from both quantitative and qualitative perspectives. The most important result highlighted is that in those countries complete education does not guarantee one masters reading and mathematics skills. The importance of the use of competence, specially at work, and the relevance of such variables as parents' schooling and place of birth, among others, are also stressed. At the same time, the study draws the attention to the importance of considering the Youth and Adult Education in the educational reforms, especially owing to the requirements of our information and knowledge society, under which the adult population is already working.