We are currently witness to an explosion of international academic mobility across the globe. However, can we truly speak of a student returning ‘transformed’ by his or her foreign study experience with an altered worldview? And if so, what may have triggered such changes? As international educators we face a lack of international empirically based comparative studies on the impact of a study abroad as well as how the various institutional frameworks of mobility and students’ social lives in the host country contribute to different outcomes. This dissertation is based on fieldwork in three countries (France, China and the United States) undertaken in 2010 and 2011 with a sample of 180 mobile students surveyed. The various factors at play during an academic sojourn abroad that may impact a student’s self-understanding and his/her ties to his/her country are examined. Our central question is whether students’ national identifications and the idea of the nation as conceived in each national tradition undergo transformations influenced by the relationships and social networks woven during the stay abroad. We assume that there is a link between the internationally heterogeneous composition of a network and a more open and tolerant set of national identifications. Social network analyses and an original multivariate statistical indicator measuring national identity types are used to show this link. In conclusion, we demonstrate how types of social networks impact ideas about national identity. Given the strong structural influence of mobility frameworks on student sociability, we can more accurately compare them in terms of their potential impact on students’ international understanding.