Determinants of health encompass various social, economic, environmental, and behavioral factors that collectively shape individuals’ and populations’ health outcomes. These determinants include social conditions such as economic stability, education, community support, and neighborhood safety; the physical environment, such as air and water quality; individual behaviors like diet, exercise, and smoking; biological factors, including genetics and family history; and access to health care. Each determinant influences health, and their intersection can either support or limit health and well-being. The interconnectedness of these determinants highlights their role in health promotion and illness prevention. Health promotion empowers individuals and communities to enhance their health, while illness prevention focuses on reducing risks before diseases develop. Addressing social determinants is central to these efforts, as these factors often create barriers to healthy behaviors and increase susceptibility to illness. Health promotion and illness prevention efforts also support health equity, as social determinants frequently affect marginalized communities. By improving access to resources and health care for these populations, health interventions can reduce inequalities and promote fairness in health outcomes. Understanding and addressing the full scope of determinants is essential for building a more inclusive and effective healthcare system that supports long-term, positive health outcomes across diverse communities. This chapter explores the intersection of key health factors. It begins with an overview of the concept of health determinants, followed by an examination of these determinants as a complex “web of causes” or a “causal chain.” Next, the chapter analyzes how individual, environmental, and social determinants of health interconnect. Finally, it addresses the integration of health determinants with health promotion and illness prevention.