This chapter examines the Green, Resilient, Electric, and AI-driven Transport (GREAT) System through the lens of Urbanimmunology, framing it as the circulatory and immune system of a healthy urban and regional body. Its Green component acts as a metabolic detoxifier, replacing fossil-fuel-based “diet” with renewable energy to reduce urban inflammation caused by pollution. Resilience emerges from distributed energy nodes along transport corridors, analogous to lymphoid tissues providing local defense against systemic collapse. The electric network functions as a dynamic vascular system, sustaining circulating “cells” (electric vehicles) with uninterrupted energy. The AI-driven core serves as the cognitive and adaptive nervous system, processing real-time data, learning from patterns, and coordinating calibrated responses to traffic, demand, and hazards. By integrating these elements, the GREAT system addresses chronic urban pathologies—aging infrastructure, energy insecurity, operational inefficiency, and socio-economic peripheral decline—offering a systemic, immunologically grounded pathway toward a resilient, adaptive, urban, and regional future.