Occupational Performance Coaching (OPC) is a family-centred intervention that empowers caregivers to support their children to achieve their goals and learn important life skills. The aim of this cluster randomised controlled trial is to determine if OPC is more effective than usual care for improving the participation of children with neuro-developmental disabilities, such as autism and cerebral palsy, in meaningful activities in the home, school and community. We are also undertaking interviews with caregivers about what it was like to be coached (rather than be given advice) by a rehabilitation specialist to understand how to improve OPC, for both Māori and non-Māori families. Findings will provide important information about effective interventions for working with families with children with neurodevelopmental disabilities. A range of learning resources will be available for services after the study finishes.