Introduction

The study of the cognitive and linguistic achievements of bilingual children has recently become a respectable, even popular, area of inquiry in psychology and education. The issue is not new, but its history as a serious topic of research is somewhat speckled. Researchers have indulged in speculation for some time about the consequences of bilingualism for children's cognitive development, school achievement, linguistic processing, and metalinguistic abilities, but clear theoretical connections based on sound empirical data have been rare.