This discussion of bilingualism and second language learning concerns many linguistic considerations that figure in the problem of language instruction. The author reports on current research and on the ideas of several noted linguists. Topics considered in this study are the goals of the bilingual education program, reasons for becoming bilingual, a definition of bilingualism, bilingual dominance and balance, types of bilingualism, bilingual barriers, second language study, two kinds of language learning theories, the effective teacher, and test validity. Included also are reports of observations in bilingual classrooms and conclusions based on classroom observations. The summary from a national survey of linguistic methodology is provided along with a bibliography. (VM)