Student activism can be characterized as student action for the sake of a cause. Often student activism is marked as challenging the status quo, with the greater intention of advocating for change or raising awareness. Furthermore, though student activism is often thought of as both energetic and hypervisible, student activism can take on many forms. One such form is through student unions. Here, the term student unions refers to formally established student groups with the purpose of serving as vehicles for campus activism. This entry examines the causes and contexts of campus activism and describes student unions around the world.