This chapter explores how psychological research generates evidence-based solutions to urgent global health challenges identified by the World Health Organization (WHO). It highlights psychology’s role in tackling infectious disease prevention, healthcare equity, workforce well-being, antimicrobial resistance, and the intersection of climate change and health. By examining cognitive, emotional, and social factors, the chapter demonstrates how behavioral science informs interventions to reduce vaccine hesitancy, enhance patient adherence, and improve public trust in health policies. It also investigates AI-driven patient-centered initiatives, illustrating how psychological insights optimize digital health literacy, engagement, and ethical technology adoption. The chapter presents research-led approaches to addressing misinformation, promoting inclusive health communication, and mitigating burnout in healthcare professionals. It showcases real-world case studies, including strategies for enhancing health literacy, fostering sustainable health behaviors, and supporting global health systems. As the 2030 Sustainable Development Goals (SDGs) deadline approaches, psychological research remains essential in designing effective, human-centered solutions to the world’s most pressing health challenges.