Energy security is a top priority for import-dependent countries like Poland and is driving efforts to diversify supply and reduce dependence on dominant exporters. International cooperation - through infrastructure projects, technology sharing and joint investment - is increasing resilience and accelerating the clean energy transition. This article examines Poland’s evolving international energy partnerships from 2015 to 2024 and their impact on the pace of Poland’s energy transition. This article uses a mixed-method approach, combining policy analysis, document review, quantitative data analysis, and case studies to examine how international cooperation supports Poland’s energy transition. Framed through a hybrid theoretical approach that combines elements of neoliberal institutionalism and certain aspects of realism, the study assesses how international regimes and market mechanisms influence Poland’s energy diplomacy and decarbonization efforts. The research highlights that international energy cooperation plays a critical role in enhancing Poland’s energy security, not only with a reference to security of supply but also through accelerating the development of renewable energy, and advancing key transition areas. One of the major findings is the untapped potential for collaboration in emerging sectors such as hydrogen, biomethane, and energy storage. The study also underscores the significant impact of European financial institutions. Furthermore, the author proposes a classification of Poland’s foreign energy partners into strategic, sectoral, and potential partners, providing a framework for targeted policy engagement. The author also analyses the most important obstacles and drivers for Poland’s international cooperation in the energy sector. The article concludes with actionable recommendations to strengthen and expand Poland’s international energy partnerships. Strengthening international energy cooperation is not just beneficial but essential for Poland’s secure and sustainable energy future. Unlocking partnerships in emerging sectors and leveraging EU financial support can significantly accelerate the country’s transition efforts.