This article proposes that the rise of sentient cities inaugurates an era of pervasive citizenship wherein individual citizens function as wearable devices for a collective body. To understand what rhetorical practices are available in this problematic, the article proceeds in three parts. First, it surveys how information systems help determine rhetoric through and as a kind of systems theory. Second, the article traces how technologies and techniques that form individual bodies are now emerging at larger scales and shape collective bodies. Through a series of examples, the article shows how multi-partner ventures to install data collection sensors in cities are informing a new problematic that we term #SenseCommons. Third, the project offers extra-disciplinary resources for rhetorically navigating today’s increasingly pervasive information spaces. Ultimately, this article proposes that the emergence of sentient cities introduces a system of continuous rhetoric whose primary function is not to persuade but to inform.