Withdrawal and multitreatment single subject research designs were used to evaluate the effectiveness of stay-play-talk (SPT) interventions on social behaviors of preschool-aged peers to children with disabilities. Each group included at least one socially competent peer and one child with Down syndrome who used an augmentative and alternative communication (AAC) device as a primary mode of communication. Peers were trained to use SPT strategies during free play sessions, and a modified reinforcement system and modified peer arrangement were introduced for one group. For one group, results indicate a functional relation between the original SPT intervention and increased stay and play behaviors. For the other group, results indicate a functional relation between SPT with modified arrangement and increased stay and play behaviors. Future research is needed to determine effectiveness of SPT interventions for children with disabilities who have more sophisticated functional play skills, as well as utility of creating peer dyads compared with peer triads. (author abstract)