This document discusses the need for systems thinking in developing urban resilience. It describes the urban system as highly complex with interconnected cities and rural areas. Urban resiliency itself is described as a highly complex adaptive system. The document advocates shifting from an ego-system mindset, where the wants of power holders are prioritized over transparency and social costs, to an eco-system mindset of system prosperity thinking to fulfill the needs of all within environmental means. It then outlines various methods and methodologies for applying systems thinking, including iceberg systems thinking, multi-layer network mapping, link prediction mapping, self-organizing system mapping, and collective sense-making modeling.