In the Arquitecture, Engineering, and Construction (AEC) industry, the ability to integrate and manage information is critical for organizational performance. Information networks are key for value generation, collaboration and continuous improvement, thus the great interest that they present for companies with a lean thinking approach. It is essential for companies to recognize and understand these relationships in order to exploit them and be able to manage them as any other process in order to improve transparency, flow and seek perfection. Unfortunately, they often remain invisible, unidentified. The hypothesis of this study is that a Social Network Analysis can be utilized as an effective diagnosis tool in order to make explicit an otherwise hidden flow of valuable information. The study begins with a literature review to support the analysis and understand the metrics, and the creation of a methodology for its use and application. It continues with a pilot implementation program in a mining company, enabling to test the methodology and to conclude with recommendations and possibilities of use of this tool. Future studies should continue to develop this tool in order to provide recommendations, detect possible behavioural patterns and explore other applications in the project network.