BACKGROUND: Since the early 1990s there has been a burgeoning interest in global health teaching in undergraduate medical curricula. In this article we trace the evolution of this teaching and present recommendations for how the discipline might develop in future years. DISCUSSION: Undergraduate global health teaching has seen a marked growth over the past ten years, partly as a response to student demand and partly due to increasing globalization, cross-border movement of pathogens and international migration of health care workers. This teaching has many different strands and types in terms of topic focus, disciplinary background, the point in medical studies in which it is taught and whether it is compulsory or optional. We carried out a survey of medical schools across the world in an effort to analyse their teaching of global health. Results indicate that this teaching is rising in prominence, particularly through global health elective/exchange programmes and increasing teaching of subjects such as globalization and health and international comparison of health systems. Our findings indicate that global health teaching is moving away from its previous focus on tropical medicine towards issues of more global relevance. We suggest that there are three types of doctor who may wish to work in global health - the 'globalised doctor', 'humanitarian doctor' and 'policy doctor' - and that each of these three types will require different teaching in order to meet the required competencies. This teaching needs to be inserted into medical curricula in different ways, notably into core curricula, a special overseas doctor track, optional student selected components, elective programmes, optional intercalated degrees and postgraduate study. SUMMARY: We argue that teaching of global health in undergraduate medical curricula must respond to changing understandings of the term global health. In particular it must be taught from the perspective of more disciplines than just biomedicine, in order to reflect the social, political and economic causes of ill health. In this way global health can provide valuable training for all doctors, whether they choose to remain in their countries of origin or work abroad.