Primary Health Care (PHC) is a macro-level public policy that guides the organization and operation of health systems, establishing principles such as universality, comprehensiveness, and equity. Within this framework, Primary Care (PC) functions as the first level of care, serving as the main access point and prioritizing health promotion and disease prevention across all levels. This distinction is crucial to understanding the strategic roles of each component in constructing efficient and effective systems. Prevention in PC involves practices aimed at avoiding the onset and progression of diseases through healthy lifestyle promotion, early risk identification, and educational actions. Despite its transformative potential, the implementation of PHC as public policy and PC as a daily practice faces structural and operational challenges. This paper critically analyzes the role of PC in prevention, based on a literature review, and discusses its transformative potential for collective health.