Cybersecurity threats represent a persistent and escalating operational risk, particularly for Critical National Infrastructure (CNI) [1]. Existing cybersecurity maturity models often lack the necessary adaptability and intelligence to keep pace with the perpetually evolving threat landscape [2] [3]. This paper introduces the Adaptive Organizational Cybersecurity Maturity Model (AOCMM), an innovative framework developed using the Design Science Research (DSR) methodology [4]. The AOCMM integrates principles of adaptability, machine intelligence (MI), and continuous improvement to provide a systematic framework for assessing and enhancing the cybersecurity resilience of CNI organizations. The model’s primary contribution is a unified, real-time measurement instrument that facilitates a nationwide or sectoral perspective for comparing maturity levels, thereby guiding optimal cybersecurity investment and policy decisions.