The means for ethnic language retention (ELRET) should be built into bilingual education programs in the United States. Currently there are very few programs designed to help a foreign speaker maintain his mother-tongue ability as he learns a new language. Materials designed in this field should take advantage of the concept of "domain stability," i.e., the theory that an ethnic language will be retained as long as it continues to be the preferred language within definite areas of activity. Instructional materials should induce speakers to stabilize certain domains in which the ethnic language would be used in their daily lives. This report discusses research conducted in this field and programs and materials that are available. (VM)