Social skills training has been recommended as an intervention for students having difficulty establishing meaningful social relationships with peers and teachers in school settings. Several meta-analyses of the relevant literature have shown weak to moderate effects, whereas other syntheses have shown somewhat larger effects. The meta-analyses show that the typical social skills intervention averages 2.5-3.0 hours per week for 10-12 weeks for a total of approximately 30 hours, which may be insufficient to remediate long-standing social skills deficits. The current study identified students who were homogenous on the type of social skills deficit (i.e., acquisition deficits) and provided them with intense (60 hours) social skills training and classroom-based interventions. Students receiving intense social skills instruction showed rather large decreases in competing problem behaviors that were maintained at two-month follow-up and that were socially validated by substantial pretest/posttest changes in teacher ratings of social skills and competing problem behaviors.