In a modern, calculative world, the techniques of tracking are steadily increasing everywhere. Augmented by algorithmic procedures and analytics, they have been incorporated into distributed network systems, augmented by new sensing and locationing technologies, and embedded into all manner of mobile devices, urban structures and environments. As the urban realm is understood through the spatialization of algorithmic operations, with all phenomena converted, standardized, and rendered interoperable within calculative architectures and procedures, it is endowed with cognitive and agential abilities – able to track, sense and respond to phenomena with a degree of autonomy – in ways that complicate conventional ontological distinctions and political orientations. This essay offers new formats of analysis for these calculative practices and the agential and ontological status of new hybrid urban entities that they register and engender. The key analytical tool and structuring principle introduced is that of "program" – an organizing and standardizing practice that moves beyond algorithmic-based understandings. The challenge is to grasp what "program" registers and demands within the calculative paradigm of tracking, while at the same time understanding how this can be opened up, made flexible, the struggle for its terms resituated. From this basis, a politics of program can be oriented around the constitution of the event.