This paper is one of ten that were commissioned to investigate research needs and to stimulate planning activities. Two underlying assumptions of this paper are that all Americans should have the opportunity to develop an ability to speak, read and write English well, and that all Americans should be encouraged to maintain or acquire a second language. Recent research has revealed the enriching effects that bilingualism can bring to an individual and a society. The International Education Division of ED has supported research and materials development efforts for certain of the less commonly taught languages. It is argued that a great deal more work needs to be done on less commonly taught languages, effective second language learning and teaching, the retention or reinforcement of language skills once acquired, and language loss. Eight major foci for research and materials development are identified. Of those, three are considered to be of immediate concern and of high priority for NIE: (1) a continuing examination of factors associated with second language learning in diverse pedagogical or social settings; (2) the development of a new set of testing devices; and (3) an examination of language skill attrition involving basic psycholinguistic research directly concerned with language skill loss. (Author/AMH)