Association rules mining is one of the the most relevant techniques of data mining. It has been also applied in the domain of text mining, but the results are hard to interpret. In this matter, an Association Network is an structure to represent as a graph the relationships mined as association rules. The goal of this project was to provide a methodology to build association networks from concepts extracted from a collection of documents, as well as the study of the mathematical properties of the association networks to prove that they are not random graphs and that they exhibit small-world properties.