Countering the drive to erect walls between nations and communities, the burden is increasingly on educators to develop in students essential skills and dispositions for a more hospitable future. Global education is essentially aimed at addressing the realities of increasingly networked societies and porous exchanges of knowledge, capital, and products among people and groups around the world. This paper examines how global education is enacted in two schools in Singapore and the United States. Given that a central characteristic of the twenty-first century is globalization, global education is inevitably embedded in the discourse of twenty-first century competencies utilized by policymakers worldwide. However, while global education has typically been studied as a singular subject such as Human Rights or integrated into History, Social Studies, or Civics Education, this study differs as it examines two schools that have adopted a whole-school approach to global education. That is, global education is embedded in the culture of schooling and infused across curricula subjects. The first part of the paper provides an overview of global education and its two key emphases--globalism and global citizenship. The second part discusses the tensions emerging from observations of global education in the two schools.