This paper explores whether the notion of 'global citizenship' is too abstract to be valuable in driving curriculum policy and active citizenship for students. The paper looks firstly at three of the key aspects of an active role: a concern for social justice; rights; and culture and cultural conflict. It then examines actual curricula and programmes of study for global citizenship, and compares the conceptual frameworks, progression routes and emphases within these curricula. It moves on to review the research on teachers' practices and orientations in teaching global citizenship, finding some variation and problems, particularly in areas such as teaching controversial issues. Factors in successful impact of global citizenship education are outlined, such as various forms of democratic decision-making and community service. Constraints are nonetheless identified of curriculum overload, resources, time and confidence. The paper then describes existing research on the needs and wishes of learners within global citizenship. The conclusion confirms the consensus on the importance of global citizenship and argues that it can be turned into a more radical and politicised curriculum area; however, more research is needed on impact of the learning, including research by students themselves.