Transit-oriented development (TOD) has become a key pathway toward sustainable urban transformation by enhancing resource efficiency and promoting compact city design. High-density development around transit hubs not only reduces automobile dependence and optimizes land and energy use but also facilitates the coordinated management of essential resources—such as water, electricity, and land—within the framework of the Urban Nexus, thereby alleviating ecological stress and reducing carbon emissions. Furthermore, TOD increasingly reflects an integrated environmental dimension that bridges the ecological (natural system resilience) and carbon (human-induced pressure) aspects into a unified “environment” perspective. This chapter examines the interconnections among compact cities, TOD, and urban ecology by proposing two analytical frameworks—the Node–Place–Ecology (NPE) and Node–Place–Carbon (NPC) models—and further extends them to an environment-centered evaluation paradigm. Using empirical evidence from the Tokyo Metropolitan Area, the study reveals multi-scalar sustainability transitions across urban cores and suburban contexts. The results demonstrate that incorporating the environment dimension helps achieve a dynamic balance between transportation, land use, and resource systems, offering new analytical insights and policy implications for developing compact, low-carbon, and resilient metropolitan regions.