Independent toileting is a critical functional life skill. Unfortunately, acquisition of this skill is often delayed in children with Autism Spectrum Disorder. Interventions based on behavioural principles are often used to toilet train children. Methods that incorporate behavioural components, including systematic prompting and reinforcement contingencies, have yielded positive results for teaching toileting skills to children with disabilities. The purpose of the present study was to determine whether selected procedures based upon a behavioural model would be effective in teaching an 8-year-old boy with autism independent toileting skills, including in-toilet defecation. A secondary goal of the intervention was to reduce interfering behaviours associated with toileting. In-toilet defecation increased as a result of the intervention.