The international debate on resilience has grown around the ability of a community to prepare for and adapt to natural disasters, with a growing interest in holistically understanding complex systems. Although the concept of resilience has been investigated from different perspectives, the lack of understanding of its conceptual comprehensive aspects presents strong limitations for spatial planning and for the adoption of policies and programs for its measurement and achievement. In this paper, we refer to “territorial resilience” as an emerging concept capable of aiding the decision-making process of identifying vulnerabilities and improving the transformation of socio-ecological and technological systems (SETSs). Here, we explore the epistemology of resilience, reviewing the origins and the evolution of this term, providing evidence on how this conceptual umbrella is used by different disciplines to tackle problem-solving that arises from disaster management and command-control practices to augment the robustness. Assuming the SETSs paradigm, the seismic and structural engineering, social sciences and history, urban planning and climatology perspectives intersects providing different analytical levels of resilience, including vulnerability and patrimony from a community and cultural perspective. We conclude that territorial resilience surpasses the analytical barriers between different disciplines, providing a useful concept related to complex problem-solving phenomena for land use planning, opening a new research question: how can territorial resilience be measured, acknowledging different units and levels of analysis aiding decision-making in spatial plans and projects? In attempting to understand a resilient system, quantitative and qualitative measurements are crucial to supporting planning decisions.