The majority of research on prosody in conversation to date has focused on exploring the role of individual prosodic features, such as certain types of pitch accent, pitch register or voice quality, for the accomplishment of specified social actions. From this research the picture emerges that when it comes to the implementation of specific actions at specific sequential locations conversationalists employ prosodic features systematically, but also with considerable variation, and indeed flexibility. This paper suggests a further line of enquiry, which pursues a wider, more fundamental role of prosody for interaction, and which does not focus on individual prosodic practices or features, but on participants' collaborative use of prosody for the implementation of one of the most basic interactional decisions: whether to continue a previously established action trajectory, or whether to start a new one. The data and findings of recent research make it clear that prosody, and in fact talk-in-interaction as such, is not appropriately defined by reference to individual features, speakers, locations and actions alone, but must be approached as a resource and negotiating strategy for social "inter"action. Prosody, therefore, must be described according to its role for both the accomplishment, and the "coordination" of actions across turns and participants. (Contains 1 figure and 3 notes.)