The fourth edition of this bestselling text provides a comprehensive discussion of single case research methodology, with updated information throughout the book, including new content on design types, design selection, social validity, fidelity, generality, visual analysis and writing. Students, researchers, and practitioners can use this detailed reference tool to conduct single case research design studies; interpret findings of single case design studies; and write proposals, manuscripts, or systematic reviews of single case methodology research. The new text features updates relevant to contemporary guidelines about single case research and includes examples of recent and historical studies in education and behavioral sciences.