One of the most exciting topics at the frontier of high energy particle physics and cosmology is understanding the nature of dark matter. Observing its production and measuring its properties in high-energy particle collisions is a topic of high priority at the Large Hadron Collider. Many searches have already been undertaken and are ongoing, but have not yet observed dark matter. I will discuss the motivations for a new approach to searching for such invisible phenomena at the LHC. I will present the first results of such a measurement from the ATLAS experiment, placing them in context with existing approaches, discuss their implications, and give my perspective on the future of this measurement programme.