This paper sets out to provide a preliminary descriptive account of an important sub-sector of the Argentine education system: those schools locally known as 'bilingual schools' or 'colegios bilingües'. We suggest that the label 'bilingual' has, at times, been applied rather loosely to a number of institutions. For current purposes, we restrict the scope of this study to schools that aim to teach through the medium of two languages. These schools may be characterised both in terms of the shared features that set them apart from other schools in Argentina, and in terms of the distinctions among them, which make this a diversified sub-sector. Broadly speaking, the schools in this sector match the criteria proposed by Johnson and Swain (1997) in their study of immersion education. The similarities across this sector of schools include a broad adhesion to a model of enrichment with the expected language outcome of bilingualism, biculturalism and biliteracy; the use of a parallel or integrated curricula; the use of external examinations as a form of validation. Among the distinctions we find across schools we can mention their relative age, size, educational levels covered, variation in level of fees, legal status, curricular offerings, and the composition of their staff.
All the schools studied fall within the private education sector and had their origins in the community schools set up by different groups of immigrants. These schools have transformed over time since they were founded in the nineteenth century, evolving from what were originally Heritage Schools (see Cummins, 1995) to Dual Language Schools (Lindholm-Leary, 2001) and, ultimately, to a new form of Bilingual school we label the 'Global Language' School, chiefly characterised by its aim to provide a broad educational programme that prepares children to take part in the decision-making stratum of a globalised world (Belle-Isle, 1986 and Gellar, 1981). This international perspective has ramifications on the curricular decisions made by the schools.
A further aspect of this development is the impact of English as a global language (Graddol, 2000). On the one hand, this partly explains the proliferation of English-Spanish bilingual schools as the perceptions of the importance of English spread across the society. On the other hand, we can see the impact of English on the other bilingual schools where English is included in the curriculum and presented as an important complementary aspect of school's programme, sometimes facilitated by a move towards the integration of the local and foreign or international curricula.
We conclude by surveying some recent trends within the Argentine bilingual school sector such as the weakening of direct cultural connections with a particular country, as opposed to an international outlook and provision of a broad educational experience. In this context, the question of staffing and specific teacher training for these contexts becomes a central issue. We also outline some possible avenues for further research.

References
- Cummins, James (1995) "Heritage language teaching in Canadian schools." In: O. García & C. Baker (eds.) Policy and Practice in Bilingual Education: Extending the Foundations. Clevedon: Multilingual Matters. (pp. 134-138).
- Johnson, Robert K. and Merrill Swain (1997) Immersion Education: International Perspectives. Cambridge: Cambridge University Press.
- Lindholm-Leary, Kathryn (2001) Dual Language Education. Clevendon: Multilingual Matters.

This paper will appear as part of the forthcoming International Journal of Bilingual Education and Bilingualism Special Issue - Bilingual Education in South America - Guest Editor: Anne-Marie de Mejía.