The primary purpose of this book is to offer a broad-based examination into the role of scientific inquiry in contemporary special education. As with the first two editions, which were published in 2001 and 2011, the goal is to provide a comprehensive overview of the philosophical, ethical, methodological, and analytical fundamentals of social science and educational research. Aspects of special education research that distinguish it from scientific inquiry in other fields of education and human services are specified. Foremost among these distinctions are the research beneficiaries-children with disabilities, their parents, the special educators; availability of federal funds for research and demonstration projects that seek to improve educational outcomes; and the historical, philosophical, and legislative bases for the profession of special education. This new edition represents a revision of more than 30 percent with over 250 new references. Each chapter is thoroughly updated with new developments in research topics, designs, and methods that have emerged over the past decade in the field of special education. This unique book is an excellent resource guide for graduate-level students, practitioners, teachers in the field of special education, disability studies, early intervention, school psychology, and child and family services.