A Virginia-based city resilience chief, an Australian-American terrorism expert, a Colombian crime analyst, and a UT Austin urban design professor discuss their collaboration on a project that combines handheld tech, the science of antifragility, and flows of people, things, energy, and information through cities. Motivated by experiences with war, crime, and urban social and climatic stresses, they seek to detect “disturbances in the force” to reduce threats from agents such as mass shooters and terrorists and from disastrous events. Melding diverse perspectives and emerging technologies, their goal is early detection, rapid response, system-based evolution of cities to save lives. The team explains progress so far, next steps, challenges and opportunities for their design-based approach.