PART I: MODELLING EDUCATIONAL EFFECTIVENESS AT TEACHING, SCHOOL AND SYSTEM LEVEL -- Preface -- 1. An Overarching Conceptual Framework -- 2. Modelling Teaching and Learning -- 3. Defining the Key Factors in Instructional Effectiveness -- 4. Modelling School Effectiveness -- 5. School Effectiveness Research and the Meaning of the Most Important Effectiveness Enhancing Conditions -- 6. System Level Context and Effectiveness Enhancing Policies -- PART 11 QUANTITATIVE RESEARCH RESULTS -- 7. Effects and Effect Sizes in Educational Effectiveness Research -- 8. Meta-analysis of School and Instructional Effectiveness -- 9. System Level Conditions: Miscellaneous Results -- 10. Other Syntheses of Empirical Findings -- PART III: THEORETICAL INTERPRETATION AND PRACTICAL APPLICATION -- 11. Theories on Educational Effectiveness and Ineffectiveness -- 12. Recapitulation and Application -- 13. Case Study: Quality Oriented Educational Policy in the Netherlands -- Epilogue. .This book is a critical assessment of the knowledge base on educational effectiveness, covering a period of five decades of research. It formulates a “lean” theory of good schooling, and identifies and explains instances of “ineffectiveness”, like low effect sizes of malleable conditions, for which expectations are highly strung. The book presents a systemic outlook on educational effectiveness and improvement, as it starts out from an integrated multi-level model that comprises system level, school level and instructional conditions. It offers a classification of school improvement strategies and scenarios for system level educational improvement. Above all the analysis is very systematic, comprehensive and strongly grounded in theory. The book includes a case study analysis of various strands of improvement-oriented educational policy in the Netherlands as an illustration of some of the arguments used.