This special issue of Vaccine focuses on innovations and challenges in strengthening immunization programs globally. Key themes include the integration of new vaccine technologies, such as mRNA vaccines, into existing systems, and strategies to address inequities in vaccine access. Several articles highlight the importance of data-driven decision-making, supply chain resilience, and workforce training to improve program efficiency. The issue also emphasizes the need for multi-sectoral collaboration and community engagement to sustain high vaccination coverage. Practitioners and policymakers are encouraged to adopt these evidence-based approaches to enhance the reach and impact of national immunization programs.