This is the age of the platform. This issue, the second of our special responsive issues that call for shorter, more accessible articles on key current topics, presents numerous reflections and case studies of the surveillance rationalities undergirding contemporary digital platforms. By platform surveillance, we do not simply mean surveillance that happens to be facilitated by platforms, although that is clearly significant and widespread. Our primary focus is instead on the manifold and often insidious ways that digital platforms fundamentally transform social practices and relations, recasting them as surveillant exchanges whose coordination must be technologically mediated and therefore made exploitable as data. In the process, digital platforms become dominant social structures in their own right, subordinating other institutions, conjuring or sedimenting social divisions and inequalities, and setting the terms upon which individuals, organizations, and governments interact. Digital platforms, in this sense, clearly operate as markets, not simply as market competitors (Pasquale 2017a). More than that, though, the emergent forms of platform capitalism portend new governmentalities, as they gradually draw existing institutions into alignment or harmonization with the logics of platform surveillance while also engendering subjectivities (e.g., the gig-economy worker) that support those logics. This depiction should not be read as facile technological determinism. After all, recent legal restrictions placed upon platforms like Airbnb and Uber by cities demonstrate that platforms are subject to mediation, just as the grotesque supplication of cities courting Amazon’s “HQ2” reveals obvious complicity in the face of these pressures. Instead, this description, and indeed this special issue, is offered as a recognition of profound shifts that are underway with the advent and increasing centrality of digital platforms. Because surveillance is essential to the Editorial Platform Surveillance Murakami Wood & Monahan: Platform Surveillance Surveillance & Society 17(1/2) 2 operations of platforms, because it structures the forms of governance and capital that emerge, the field of surveillance studies is uniquely positioned to investigate and theorize these phenomena.