David A. Koppenhaver, Ph.D., is Professor in the Reading Education and Special Education Department at Appalachian State University. His research focuses on literacy in individuals with significant disabilities, including those with complex communication needs. He and David Yoder cofounded the Center for Literacy and Disability Studies at the University of North Carolina at Chapel Hill in 1990. Karen A. Erickson, Ph.D., is Yoder Distinguished Professor and Director of the Center for Literacy and Disability Studies at the University of North Carolina at Chapel Hill. A former teacher of children with significant disabilities, Dr. Erickson's current research addresses literacy and communication assessment and intervention for students with a range of disabilities, including significant disabilities. Dr. Erickson is codeveloper of the Tar Heel Reader online library of accessible books for beginning readers as well as several other assistive, learning, and communication technologies.