Response interruption and redirection (RIRD) often results in a reduction in level of vocal stereotypy in children and adolescents diagnosed with autism spectrum disorder (ASD). However, research is still needed on the effects of RIRD on adults and on the mechanism by which RIRD produces its effects (i.e., punishment vs. differential reinforcement). The current study used an uninterrupted data collection procedure to evaluate the effects of RIRD, and specifically the contingent demand component, in an adult participant. Results showed that motor RIRD was effective in reducing vocal stereotypy when the demand aspect (i.e., redirection) was included but was ineffective when neutral talking (i.e., interruption) was presented. The impact of RIRD on appropriate vocalizations is also discussed.