Frontmatter -- Contents -- Contributors -- Introduction -- 1. Shifting Perspectives on Bilingualism -- I. Early Bilingualism -- 2. Early Bilingualism: From Differentiation to the Impact of Family Language Practices -- 3. Speech Perception in Simultaneously Bilingual Infants -- 4. Early Lexical Development in Bilingual Infants and Toddlers -- 5. Code-Switching in Childhood -- II. Factors Affecting Bilingualism Across the Lifespan -- 6. Quantity and Quality of Language Input in Bilingual Language Development -- 7. Factors Moderating Proficiency in Bilingual Speakers -- 8. Age of Onset of Bilingualism Effects and Availability of Input in First Language Attrition -- 9. Age of Second-Language Acquisition: Critical Periods and Social Concerns -- 10. Code-Switching in Adulthood -- III. Academic Achievement and Literacy in Bilinguals -- 11. Bilingualism and Academic Achievement in Children in Dual Language Programs -- 12. Literacy in Adulthood: Reading in Two Languages -- IV. Cognitive Effects of Bilingualism -- 13. Cognitive Effects of Bilingualism in Infancy -- 14. Bilingual Speakers' Cognitive Development in Childhood -- 15. Cognitive and Emotional Effects of Bilingualism in Adulthood -- 16. The Contribution of Bilingualism to Cognitive Reserve in Healthy Aging and Dementia -- V. Conclusion -- Concluding Remarks and Future Directions -- Index -- About the Editors