Parent-teacher rating discrepancies in rating of children's social skills were examined in a low-income, ethnically diverse preschool sample, using the Social Skills Improvement System-Rating Scales [Gresham, F. M., & Elliott, S. N. (2008). Social Skills Improvement System - Rating Scales. Minneapolis, MN: Pearson Assessments]. Participants included 663 preschool children (326 male, 336 female, M = 3.51 years, SD = 0.50) rated in the Fall of their preschool year. Children were drawn from 68 classrooms in 13 preschool sites. The results indicated that mean parent ratings were significantly greater than mean teacher ratings for the Social Skills Scale. The mean parent-teacher ratings were not significantly different for the Problem Behaviours Scale. Follow-up analyses indicated that parent-teacher ratings differed across six of the seven Social Skills sub-scales. These differences were significantly associated with family income. Implications for parents, teachers, and educational policy are explored. (author abstract)