A comprehensive understanding of the socio-demographic, clinical, and biological characteristics of patients with heart failure is essential to develop novel strategies for improving outcomes. The identification of the barriers to guideline-directed medical therapy implementation in a real-world setting is critical to decreasing the risk of heart failure hospitalization and mortality. A comprehensive and well-designed heart failure registry can determine the clinical characteristics of patients with heart failure, identify patient, physician, and healthcare system-related factors for the non-use of evidence-based therapies, and improve the implementation of guideline-directed medical therapy. It should be noted that the number of heart failure registries that enroll patients with de novo heart failure, chronic heart failure (outpatients), and worsening of heart failure (hospitalized or treated in the emergency department), with all three relevant ejection fraction categories (heart failure with reduced ejection fraction, heart failure with mildly-reduced ejection fraction, and heart failure with preserved ejection fraction), is limited. Furthermore, only a few registries assess detailed aspects of guideline adherence, treatment decisions, and both in-hospital and long-term outcomes. Therefore, the Türkiye Heart Failure (TURK-HF) registry has been designed to address this gap in knowledge about the identification, management, and long-term prognosis of patients with heart failure in a real-world setting.