Token systems often involve a predetermined number of tokens required prior to exchange for a terminal reinforcer. The effectiveness of token systems implemented in this manner has been well documented within the literature; however, some have discussed the possibility of a fixed earning requirement creating a context in which the learner no longer emits the desired behavior once the terminal number is achieved. A possible alternative to a fixed earning requirement is selecting the earning requirement based upon learner responding and leaving the requirement unknown to the learner until the moment of exchange. The purpose of this study was to evaluate the effectiveness of a token system with a flexible earning requirement to increase the frequency of comments during snack for 3 children diagnosed with autism spectrum disorder. The results of a nonconcurrent multiple-baseline design demonstrated the flexible token system was effective at increasing the rate of comments in addition to the cumulative number of novel comments.
