With the passage of Public Law 94-142 in 1975, the learning disability construct gained national legitimacy. Feeding that political achievement, behind the very idea of a learning disability, was the development of a science that blended neurology, psychology, and education. This book tracks the historical creation of the science of learning disabilities, beginning with the clinical research with brain-injured World War I soldiers conducted by German physician Kurt Goldstein. It traces the growth of the two primary research traditions, the psycholinguistic theory of Samuel Kirk and the movement education of Newell Kephart, exploring how specific scientific orientations, theories, and practices led to the birth of the learning disability in the United States.