Aim Despite evidence that effective cancer care coordination has yielded positive results in facilitating and supporting high-quality care, it remains a complex and challenging system to implement. South Africa’s mortality of lung cancer is reported at 13.4%, ranking highest among all cancers. Coordinating the care of cancer patients is complex and can last several months or years, with multiple consultations, rounds of treatment, and follow-up in various settings. With so many health professionals, services, and settings involved, the care of these patients can become fragmented and uncoordinated. This interface between primary and specialty care offers a valuable opportunity to appreciate the challenges of delivering well-coordinated cancer care. Consequently, this paper explores healthcare professionals’ perspectives on coordinating lung cancer care within and between healthcare services. Methods This study was conducted through virtual, telephonic, and face-to-face in-depth interviews with 26 purposively selected participants from primary to tertiary health professionals, using a semi-structured tool and drawing from grounded theory design. Data generation and analysis were conducted iteratively, followed by systematic thematic analysis to organise data, review, and interpret the findings. Findings The overall public health system challenges reported by participants involved service fragmentation, staff shortages, and communication problems. Drivers of lack of care coordination varied widely across healthcare professionals, with interoperability and communication challenges standing out as the most prominent themes. Consequently, better communication, interoperability, and improved care transitions between providers and health systems were proposed. This study provides pertinent information for policymakers and healthcare professionals to develop appropriate strategies for improving cancer care coordination interventions. Conclusions A fundamental change is required to shift the direction of the KwaZulu-Natal public health system towards responsive, patient-centred, comprehensive, and coordinated care. Enabling the primary healthcare level to play a substantial role in care coordination may provide a plausible intervention to circumvent healthcare complexities.