Observing naturally occurring talk-in-interaction in Japanese, this book examines how Japanese speakers segment their talk into relevant interactional units and use particles such as <i>ne</i> and <i>sa</i> to accomplish local pragmatic work. The study provides a conversation analytic, action-oriented account for the ubiquity of such particles in Japanese talk.<br />The study argues that such particles are important resources for Japanese speakers to negotiate and fine-tune particular conversational contingencies within the emerging sequential environment of the talk. Various examples show that prospective alignment and the negotiability of conversational next action are ever-present issues for Japanese conversationalists and are handled at the precise moment of their relevance through interlocutors’ deployment of <i>ne</i> and <i>sa</i>. This study thus adds to the literature on Japanese conversational interaction a novel understanding of particle use in its synthesis of functional linguistics and conversation analysis.