Contents -- Figures and Tables -- Abbreviations -- Acknowledgements -- Part 1. The Research of Willingness to Communicate in a Second Language -- 1. Introduction -- 2. Hybrid Perspectives on WTC in an L2 -- Part 2. The Big Picture: Interrelationships between WTC, Communication Confi dence, Motivation, Learner Beliefs and Classroom Environment (Phase 1: Questionnaire Survey) -- 3. Dimensions of WTC, Confidence, Motivation, Beliefs and Classroom Environment -- 4. Interrelationships between WTC, Confidence, Motivation, Beliefs and Environment on WTC: A Full Structural Model -- Part 3. A Situated Lens: WTC Fluctuations over Time and Across Classroom Situations (Phase 2: A Multiple-Case Study) -- 5. Four Cases and their WTC Fluctuations -- 6. Distal and Proximal Influences on WTC Fluctuations -- Part 4. Blending 'Apple Juice' and 'Orange Juice': Integration of Overall Findings -- 7. WTC Inside the Language Classroom and Beyond -- 8. Concluding Remarks -- Appendix 1: Factor Loadings -- Appendix 2: Questionnaire -- Appendix 3: Correlation Matrix for the Structural Model -- Appendix 4: Interview Guide -- Appendix 5: Classroom Observation Scheme -- Appendix 6: Learning Journal Framework -- Appendix 7: Coding Scheme