This study investigated the level of social valence and type of social behaviors expressed in 15 children with specific language impairment as they engaged in typical language intervention activities during conversation-based and imitation-based language programs. These programs were both applied to each child over a period of several weeks. Videotapes of treatment sessions were analyzed for the presence of five verbal and 11 nonverbal behaviors selected to measure social valence. In addition, the child's level of social valence was scored on a three-point rating scale. The results showed that although both types of treatments were predominantly associated with positive social valence ratings and a high frequency of smiling, laughing, and engagement in the activities, a significantly higher number of these positive ratings and behaviors were noted within conversation-based treatment. In contrast, although negative social valence ratings and expressions of boredom or dislike were very rare, these were observed more frequently under imitation-based treatment. There was a significantly higher rate of verbal initiations in the conversation-based treatment, and a significantly higher rate of quiet, passive participation in the imitation-based treatment. The findings are discussed in relation to treatment selection and viable strategies for assessing treatment acceptability in children.