Advances in the definition of social skills deficits in children and youth with learning disabilities are presented and critiqued. The proposed modified definition of learning disability by the Interagency Committee on Learning Disabilities, which includes social skills deficits as a specific learning disability, is presented and discussed. This definition is analyzed from primary, secondary, and social learning theory causative hypotheses. Development of an adequate assessment technology is viewed as critical to the identification and classification of social skills deficits in children and youth with learning disabilities.