This report, prepared for the USAID/Senegal Mission, summarizes applicable research on education in multilingual contexts and on the use of L1-based, bilingual instruction in particular. It also briefly presents the education and sociolinguistic environment in Senegal, as well as a summary of relevant national language education programs in the country. Lastly, the report makes recommendations aimed at supporting a transition toward the use of national languages for instruction in primary schools.Both the research and recommendations presented in this report are based on a review of applicable evidence on language use in education, particularly as it relates to bilingual instruction in multilingual contexts. The information included in this report draws from that assembled in a larger document prepared for USAID, Planning for language use in education: Best practices and practical steps to improve learning outcomes (RTI, forthcoming). Readers of this report are encouraged to refer to this document for more in-depth information on specific topics. Lastly, information on Senegal-specific programs was gathered via personal communications and a search of publicly available reports (for a list of organizations and individuals contacted, see Annex B).