ASEAN and Japan share a robust and multifaceted partnership that has evolved over five decades, and that is grounded in mutual respect, trust and shared values. The establishment of the Comprehensive Strategic Partnership in 2023 further solidifies their commitment to advancing cooperation in traditional areas while expanding into emerging domains such as digital transformation and sustainability. In the security domain, Japan has consistently prioritized ASEAN's centrality in the regional order, even as it aligns with the United States and participates in frameworks like the Quad. Initiatives such as the Japan-ASEAN Ministerial Initiative for Enhanced Defense Cooperation (JASMINE) and the Overseas Security Assistance (OSA) framework demonstrate Japan's evolving approach, transitioning from traditional capacity-building to a broader focus on enhancing maritime security, conducting joint exercises, and providing non-offensive defence equipment to ASEAN countries. The partnership's new emphasis on 'co-creation' marks a transformative shift through public and private sector collaboration to address pressing socio-economic challenges. By fostering innovation and co-developing solutions in areas like green energy, digital trade, and healthcare, the co-creation model underscores ASEAN and Japan's shared commitment to inclusive and sustainable development. Looking ahead, the ASEAN-Japan partnership is well-positioned to navigate the complexities of an evolving geopolitical landscape. By harnessing Japan's expertise in advanced technology, infrastructure development, and healthcare systems to address ASEAN's evolving priorities, and by leveraging on Japan's role as a stabilizing force amid intensifying major power rivalries, this partnership will become pivotal to the fostering of long-term regional stability, resilience, and inclusive growth.