This chapter formulates the basic problem addressed in this book: how to understand the complexity of argumentation, that is, how argument and communication are entangled in human activity. Polylogue is introduced as a simple yet perspicuous term for renewing and advancing inquiry of argumentation in complex communication. The fact that polylogue cannot be dismissed is evident in examples of managing disagreement under polylogical conditions both contemporary (e.g., social media platforms) and historical (e.g., establishing congressional representation for the newly formed US republic). While recognized in practice, however, polylogue is theoretically dismissed by an analytic strategy of dyadic reduction prominent across time in the study of argumentation and communication. Even the remarkable theoretical and methodological contributions of the twentieth-century revival of the study of argumentation as a communicative, situated practice, do not yet make a polylogical turn for understanding argumentation due to lingering commitments to a paradigmatic norm of dyadic interaction. However, much broader considerations of how argument happens stimulated by this revival provide starting points for a polylogical alternative.