We conducted three studies which examined the performance vs. skill acquisition model of social skills deficits. In Study 1, baseline social behaviors for a random sample of 12 boys with comorbid emotional and behavioral disorders (EBD), learning disabilities (LD), language delays, and Attention Deficit Hyperactivity Disorder (ADHD) revealed that prosocial behaviors as well as inappropriate behaviors exist comorbidly in behavioral repertoires, supporting a performance rather than acquisition model of social competence difficulties. In Study 2, an ABAC design was used to examine the efficacy of a self-management intervention with noncontingent (B) and contingent (C) reinforcement for three elementary aged boys with EBD. Generalization was demonstrated in natural settings for the contingent reinforcement phase only, but was not observed over time. Study 3 replicated Study 2's procedures using an ABAC multiple baseline across participants design with a sample of adolescents with varying degrees of mental retardation. Two of the three participants responded favorably to the self-monitoring training and showed marked improvements in prosocial play skills during recess; for the third participant, no behavioral changes were observed. Results from all three studies are discussed from a social learning theory perspective. The efficacy of the data collecting procedure and implications of the results are discussed. © 2007 Wiley Periodicals, Inc. Psychol Schs 44: 351–372, 2007.