A study identified discourse patterns in potential disputes, deflected disputes, incomplete, and completed disputes from a one-hour conversation involving two 3-year-old female children and one female adult. These varied dispute episodes were identified, coded, and analyzed using a pragmatic model of adult argumentation focusing on the structures, speech acts, and participant roles involved in argumentative discourse. Results indicate that (1) children learn the appropriate speech acts of argumentation at an early age; (2) children learn the underlying discourse rules and roles of argumentation early, and are able to apply them in defense of viewpoint; (3) children display only simple argument structure in their disputes but can appropriately participate in complex and compound arguments; and (4) the adult role as mediator or rational judge plays a major role in child-peer and child-adult disputes. An expansion of this pragmatic model of argumentation for application to child language must account for the pivotal adult mediator/judge role in dispute episodes. The importance of incorporating analyses of the interaction of child and adult registers into a general theory of argumentation discourse is also considered. (MSE)