According to the World Health Organization, the preferred model for organizing health systems is People-Centred Integrated Care (PCIC), in which Primary Health Care (PHC) plays a central role. In Brazil, the Ministry of Health identifies the Family Health Strategy (FHS) as the preferred model for delivering PCIC. However, multiprofessional and transdisciplinary undergraduate education within high-quality FHS services—guided by trained professionals and team-based PCIC—is still far less common than training in hospital or specialized outpatient settings.Undergraduate students from the University of São Paulo, spent one year immersed in a PHC unit with four family health teams. The unit, managed by the FMRP-USP/HCFMRP-USP academic health complex, covers a territory of roughly 12,000 socially vulnerable residents. Students received an initial transdisciplinary theoretical foundation on PCIC and subsequently followed family physicians in their daily activities.The project offered longitudinal, hands-on exposure to real PCIC practice within an academically managed PHC service. It enabled students to critically examine how family medicine operationalizes integrated, person-centred care in vulnerable territories, highlighting nuances rarely addressed in traditional hospital-based training.Interviews and clinical observations revealed the complexity of caring for vulnerable patients—especially older adults—who often face multimorbidity, economic hardship, limited education, isolation, and fragile support networks. Students learned that effective care requires understanding the person’s life story, context, and functionality. They also identified the unequal distribution of chronic diseases across social groups and the centrality of person-centred rather than disease-centred approaches.Throughout the year, students deepened their theoretical and practical understanding of PHC and family medicine. They recognized that family medicine is essential for: ensuring universal access grounded in the person, family, and community; coordinating longitudinal care across services and levels of the health system; enabling comprehensive care through multiprofessional teamwork.The project strengthened students’ humanistic and integrative training in health care. It fostered transdisciplinary learning spaces focused on value-based care, person-centred clinical method, interprofessionality, integration of public and family health, health promotion, prevention, rehabilitation, palliative care, avoidance of iatrogenesis, and the interplay of biological, psychological, social, and relational dimensions, including clinical communication and motivational interviewing.