This book sets out to present some aspects of Bilingualism, and shed light on its long-term effect on the individual, and in a wider sense, on societies as a whole. It is aimed at students setting out on their studies of languages, linguistics and teacher training courses, as an introduction and background reading; it will also be of interest to policy makers, examination planners and designers of bilingual education programmes; it might also become a source of inspiration for anxious parents, looking for guidance on bringing up their children bilingually. Last, but not least it will appeal to the casual reader, looking for clarification of certain issues and assumptions connected with bilingualism, the long term influences and effects on the individual, and provide a starting point for further investigation.