Graduate and professional TESOL students will welcome this research methods textbook for undertaking qualitative, naturalistic and action research projects. Uniquely, the book offers a three-level structured progression, suited both to novice and intermediate students with a focus on development as classroom teachers of English, and to advanced students engaged in academic research work in applied linguistics. Every chapter is structured to develop the important skills for undertaking QI in a rigorous and serious way, at whatever level is appropriate for the reader's purpose. The book is both scholarly in approach and written in an engagingly direct and clear style.