The PMBOK® Guide identifies 49 processes of project management that are instrumental to project success. To find the level of real integration of processes, the relationship between the 49 processes that compose it is analysed through the technique of social network analysis (SNA). SNA focuses on the structure of links within a set of actors, e.g., groups, people, organisations, or the products of human activity or knowledge such as websites. This technique uses graph theory to explain relationships to from mathematical indicators. The PMBOK® links their processes effectively and thanks to this research it is evident that there is a strong relationship of reciprocal dependence between each process.