Differential reinforcement of other behavior (DRO) is a commonly used reinforcement-based system for reducing problem behavior. DRO systems are particularly useful in that they are effective for the treatment of maladaptive behavior and can be individualized based on the needs of the learner. One possible way to enhance the effectiveness of DRO systems is the use of signaled delays. In the present study, the effectiveness of signaled and unsignaled DRO systems was compared for the treatment of stereotypical behavior in three adolescents and adults diagnosed with autism spectrum disorder (ASD). Results from this study suggested that while the unsignaled DRO condition was effective at reducing stereotypical behavior for one of three participants, the signaled DRO condition was effective for all three participants.