This meta-synthetic review examines the use of Action Research (AR) in Human Resources (HR), particularly in relation to artificial intelligence (AI) integration, diversity and inclusion (DI), and sustainability/corporate social responsibility (CSR). Although AR has its roots in social change and is known for connecting theory and practice, it is not widely used in mainstream HRM scholarship and practice. Based on 35 peer-reviewed empirical and theoretical studies from 2000 to 2024, this review uses PRISMA-guided synthesis to identify how AR contributes to HR transformation through participatory, iterative, and context-specific problem-solving. Key findings indicate that AR improves stakeholder engagement, promotes adaptive leadership, encourages learning organizations, and produces evidence-based, sustainable HR outcomes. The study shows that AR can enhance the implementation success of HR initiatives such as AI rollouts and DI strategies and can also influence leadership behavior and organizational culture towards inclusivity and reflection. This paper provides a comprehensive framework for HR scholars and practitioners to use AR as a strategic tool for addressing complex challenges. It also sets a future research agenda for further empirical exploration and methodological innovation in HRM.