Introduction (Relevance). The modern healthcare system is facing the problem of insufficient patient adherence to outpatient treatment, especially in chronic diseases. Failure to follow medical recommendations leads to worsening clinical outcomes, increased complications, higher rates of repeated hospitalizations, and a growing economic burden on the healthcare system. Under these conditions, the role of nursing staff as a key link ensuring continuity of care, monitoring treatment compliance, and forming sustainable patient motivation becomes increasingly important. Objective. To analyze the factors influencing adherence to outpatient treatment and to determine the role of nursing staff in ensuring it. Materials and Methods. An analysis was conducted of scientific and methodological literature, domestic and foreign studies, and regulatory documents related to the organization of outpatient care, patient adherence, and the functions of nursing staff. Systematic and content analysis methods were used. Results. Key factors reducing adherence were identified: difficulty in understanding treatment regimens, side effects, absence of symptoms, low motivation, psychological barriers, and limited access to medical services. It was established that the involvement of nursing staff — through patient education, monitoring treatment compliance, emotional support, and remote follow-up — significantly increases adherence levels and reduces the risk of relapses. Discussion. Nurses have the capacity and resources to establish trusting relationships with patients, regularly monitor their condition, and detect early signs of deterioration. Their integration into multidisciplinary teams and the use of digital tools (telemedicine, mobile applications) enhance the effectiveness of outpatient care. Conclusion. Improving patient adherence to outpatient treatment is possible with the active involvement of nursing staff possessing the appropriate competencies, which requires further development of educational programs and optimization of their professional role.