1. Preface; 2. Introduction; 3. 1. Modeling and assessing language proficiency (by Jong, John H.A.L. de); 4. Section 1. First Language Proficiency; 5. 2. The construct of grammar in early language development (by Kuiken, Folkert); 6. 3. Dimensons in grammatical proficiency (by Bon, Wim H.J. van); 7. 4. Monitoring reading and spelling achievement (by Mommers, Martin J.C.); 8. 5. Speech activity theory and reading comprehension assessment (by Bol, Eduard); 9. 6. Assessment of reading disabilities (by Leij, Aryan van der); 10. 7. Information analysis in written discourse (by Wijk, Carel van); 11. 8. Large scale writing assessment (by Blok, Henk); 12. Section 2: Multilingual Proficiency; 13. 9. Differential item functioning (by Kok, Frank); 14. 10. Assessment of bilingual proficiency (by Verhoeven, Ludo); 15. 11. Self-assessment of minority language proficiency (by Bot, Kees de); 16. 12. Exploring the second language learner lexicon (by Vermeer, Anne); 17. 13. Modeling communicative second language competence (by Verhoeven, Ludo); 18. 14. Modeling and assessing foreign language loss (by Schils, Erik); 19. 15. Dimensions in oral foreign language proficiency (by Jong, John H.A.L. de); 20. Subject index; 21. List of contributors