Integration is a concept that is referred to very widely in relation internationalization, yet its meaning is rarely explored and its benefits are often assumed. In this article, we start by reviewing the conceptualization of "integration" across different fields, notably education and the internationalization of education, intercultural communication, health psychology, and organizational studies. We propose that the varying interpretations within and across these fields can be synthesized by considering the different levels at which integration can be analyzed--individual level, community level, and institutional level. We then review the multiple benefits that integration can bring at these different levels, while acknowledging their interconnections, and noting the potential risks from ignoring integration. We end by proposing a framework to help universities and all of their members (staff and students) develop their own strategies and priorities for enhancing integration.