In a multi-year engagement, MUS executed extensive business-critical design research, usability testing, and complex human-computer interaction (HCI) design programs resulting in the creation of a new generation of screen-based (fixed and handheld) trading systems that dramatically improved trading performance, reduced training time, and reduced errors. MUS solutions were fully verified by independent usability testing. Based on HFE research and cognitive modeling, MUS formulated, for the first time, the ability to visualize equity market dynamics in terms of order flow and position balance on a single screen in a rapidly changing market. The solution dramatically reduced the cognitive workload of NYSE Specialists and Brokers while reducing decision errors in active market conditions. The solution was then adopted by exchanges/platforms worldwide. MUS executed detailed ethnographic and task analysis of trading functions on the floor of NYSE over 3-month periods. Developed hardware/display design configuration for the first successful hand-held trading systems used on the floor of NYSE. Development focused on the cognitive and biomechanical aspects of handheld device designs. Produced simulations and executed user verification testing of device configurations. The solutions were employed as templates for handheld trading device design on a global basis. The solutions saved NYSE several billion dollars based on increased order flow, reduction in trading errors, and reduction in training time for key trading positions. The MUS solution, combined with changes in equity pricing model, allowed NYSE to forgo construction of a new trading floor and related facility, saving roughly 2 billion dollars. AWARD Charles L. Mauro / MUS received the Outstanding HCI Design Award from the Association for Computing Machinery ACM for the program.