Three papers on assessment and planning in bilingual education are presented. In "Language Theory Bases," Rosaura Sanchez advocates an approach toward child bilingual education that takes into account the relationship between the parallel domains of language development and cognitive development. An awareness of this relationship is deemed necessary in order to prescribe educational strategies that can build on students' existing skills and accomplish their transfer into other domains. "Assessment/Diagnostic Practice," by Harriett Romo, addresses the practical problems of deriving the assessment information specified in the Sanchez paper. A warning is given that a language assessment situation can actually inhibit students' performance. The development of assessment instruments is discussed. "Educational Prescriptions," by Iris Santos-Rivera and Byron Williams, suggests educational applications based on language/cognition assessment data. A variety of bilingual program models are discussed, and specific educational strategies are recommended to respond to specific student needs. Appendices include: (1) an outline of subjects to be covered in a needs assessment instrument, (2) a language assessment instrument designed to determine inservice needs of teaching staff, (3) a sample sociolinguistic survey, and (4) an example of integrated thematic/language/concept lesson development. (Author/JB)