This study examines affective facial expression in conversation. Experiment 1 demonstrates that the accuracy of affect-identification for conversational facial expressions generally is no better than chance. The explanation explored by Experiment 2 is that many conversational facial expressions operate as nonverbal interjections. Thus, much like verbal interjections (“gosh,”“really,”“oh please,”“jeez,” etc.), the attribution of affect for certain conversational facial expressions should depend on their verbal context. Experiment 2 supports the notion of facial expression as interjection by demonstrating that most any conversational facial expression, regardless of Us true source emotion or of the affect it signals in isolation, tends to be interpreted according to the affect associated with the verbal context in which it occurs. In addition to the identification of context-dependent interjection as yet another function of facial expression, the study suggests a pressing need for further investigation of nonverbal behavior in natural-conversation settings.