Purpose: This article lays the foundations for the Sustainable Security Paradigm (SSP), which features national security as a holistic and synergistic complex-adaptive system that can integrate various domains of international, social, and individual activity in a long-term, sustainable fashion. The novel paradigm informs the original Sustainable Security Culture Development Cycle (SSCDC) that provides a model of transformation for organizations that wish to act sustainably in the security realm. Design/Methodology/Approach: The theoretical framework is centered around three pillars, the scientific study of the socio-ecological systems of the Anthropocene, a holistic understanding of security, and the realization of the UN's Sustainable Development Goals. During research, the study adopted the pragmatic, critical world view with the grounded theory approach and employed mixed methods of research. Case studies of the global security consequences of the COVID epidemic, the paradoxes of the 2020 Polish National Security Strategy, and the military impact on environment, provided a crosscultural and cross-contextual proof of data. Findings: Contemporary global security paradigm is unsustainable and unjust. Both in security studies theory and security policy at various levels, a shift is imperative. We need to move from a narrow understanding of security (in national security/defense terms) and replace it with a holistic and synergistic system. We also need a re-orientation of philosophical approaches, knowledge systems, principles, values, management practices, behaviors, and governance arrangements to ones that build sustainability in an increasingly interconnected, turbulent, and unpredictable world. Practical implications: The above allowed to create an operational SSCDC, designed to facilitate the transformation of security and defense organizations into institutions that continually create an environment of sustainable security and just development for all. Originality/Value: This is the first article that systemizes a comprehensive SSP, accompanied with an original and operational SSCDC.