This study examined the impact of preschoolers' knowledge of routine events, or scripts, on their conversational performance during dyadic pretend play with different discourse partners. The study was intended to investigate the success of preschoolers' communication with dyad members in matched and unmatched conditions, and to examine the ways in which preschoolers establish shared knowledge involving scripted events. Thirty preschool children, ages 4 to 5, were assigned to same-age and same-sex dyads and participated in a script-knowledge assessment and a communication assessment, each on different days. The results showed that preschoolers' interactions were more successful when both children shared knowledge of the script than when only one child had adequate script knowledge. Preschoolers accommodated discrepancies in level of script knowledge by engaging in communicative behaviors to establish shared knowledge with their partners. Older children were particularly skilled at appropriately establishing shared knowledge when needed. (AP)