There is a paucity of instruments designed to measure social competence of adolescents with autism spectrum disorders. The Social Responsiveness Scale is one of a few that can be used. This study compared differences between mother and father reports of social competence of adolescents. Data were collected from parents of 50 adolescents with and without an autism spectrum disorder diagnosis between the ages of 12 and 17 years. The Social Responsiveness Scale demonstrated high interrater reliability between parents. These results suggest that the Social Responsiveness Scale is an efficient and valuable tool for researchers and clinicians to obtain a more comprehensive understanding of an individual’s social skills deficits. Additionally, given the extremely high agreement between mothers and fathers on the ratings of their children’s social competence, obtaining data from either parent is sufficient to provide an accurate reflection of social competence at home.