This article shows how dominant actors inscribe certain ideas, visions, and predictions of infrastructural futures for international mobile telecommunications through standardization. It argues that standard setting is a key avenue that brings different (and sometimes divergent) interests, groups, concerns, and activities into alignment around a certain vision of social and technological progress. To demonstrate this, two key stages in the 5G standardization process were examined. First, we explored the path to the release of IMT-2020—the standard for 5G networks, devices, and services released by the Radiocommunication Sector of the International Telecommunication Union. Through the standard setting process, two key visions of 5G—one “evolutionary”, the other “revolutionary”—became highly influential ideas of a future worth striving for. Second, we examined how one technical feature of the IMT-2020 standard—the capacity for network slicing—was realized through the work of partner organization the Third Generation Partnership Project (3GPP). In doing so, this article reveals the processes that define the infrastructural conditions that underpin international mobile telecommunications. It also draws attention to how standardization has the potential to redefine the parameters of mobile media and communication in significant ways.