Central to all cities, communities, and military installations is the sustainability of infrastructures. Because infrastructures are intensely interconnected and interdependent, their sustainability is rooted in “systems of systems,” subject to cascading impacts as disruptions of one infrastructure spread to other infrastructures. As a result, assuring sustainable infrastructures requires an integrated perspective, recognizing not only connections between infrastructures but also connections between their sustainability and a wide range of threats and other driving forces, including but not limited to climate change. In most cases, such an integrated approach calls for broadening organizational practices to make them more participative, as well as strengthening the base of knowledge and technologies related to cross-sectoral infrastructure resilience.