Inadequate workforce resource is an ongoing difficulty across the health professions. This study proposes a train the trainer model, with the ultimate goal of improving the communication skills of children with autism. The study describes an intervention called naturalistic developmental behavioural intervention, whereby parents are trained to identify and increase opportunities for communication in their play-based interactions. Three student speech and language therapists were trained in the intervention by a skilled trainer. The students, in turn, trained the parents of three children with mild-moderate signs of autism, aged between 2.5 and 4 years. All sessions were video recorded for fidelity monitoring. Results demonstrated that the trainer and students achieved high fidelity of 97.5%. Participant parents reported the study had had a positive impact for themselves and their children. The authors propose that using this cascade approach to training could be implemented with non-speech and language therapy staff, and thereby increase access to vital training and increase opportunities for children with autism to develop their communication skills. Given the current staffing issues within health, social care and education in the UK, this evidence-based model could be essential to meeting the needs of children with autism.