The effect of immediate verbal feedback on trainer behaviour during communication training sessions with individuals with intellectual disability (ID) was assessed. Trainers were six undergraduate university students majoring in psychology. The procedure consisted of interrupting the sequence of trials of training by the supervisor and then giving brief corrective feedback. Feedback was focused on the accuracy of the following procedural aspects: (1) entry behaviour; (2) prompt level and order of presenting response prompts; (3) use of reinforcement; (4) pace of presenting trials; and (5) if this occurred, handling trainee's disruptive behaviour during training. Data were collected in a nonconcurrent multiple baseline design. Results indicated a statistically significant increase of the percentage correct trainer behaviour as compared to the baseline phase. Maintenance of effect of feedback was recorded during post-training and follow-up.