A review of available research supports the observation that the young child who lives and grows in the midst of dual language opportunities may enjoy benefits of mental flexibility or may suffer burdens of mental confusion. Further research must explore the language-thought relationship, consider the effects of dual language learning on cognitive processes and draw conclusions relevant to objectives and methods in bilingual education during the period of optimum language learning. Central to this question is a consideration of refining the mother tongue even when it is not the dominant language of the community. For those children in dual language settings, parents and teachers should keep the two languages growing in separate contexts so that coordinate language systems may result. They should provide good models and a rich background of environmental encounters. An early childhood bilingual education program will provide experiences to help children understand and relate to their environment and the larger society as well as providing language to enable the child to label, classify and store the experience for later retrieval. As the program continues, it will give due consideration to the best language of instruction in the various subject areas, the teaching of reading and writing, and the distinction between learning concepts and learning the language to express concepts. The challenge lies in guiding learners through the process so they may be competent, knowledgeable and comfortable in two environments and in two languages. (AMH)