Quality of Life in Patients with AF, Introduction: The efficacy of a treatment is based primarily on objective criteria such as mortality and morbidity, Besides these criteria, the interest in measuring quality of life in relation to health care has increased in recent years. Methods and Results: Although the concept of quality of life inherently is subjective and definitions vary, it generally is agreed that quality of life is a multidimensional construct, The impact of atrial fibrillation (AF) on quality of life has not been evaluated widely using validated methods. Therefore, an international prospective study was designed to assess quality of life over time in patients with AF using validated generic measures and specific conducted disease scales. In addition to a standard demographic questionnaire, patients will complete two predictive scales at baseline and four outcome scales at baseline, and 3-, 6-, and 12-month follow-up. An AF severity score based on subjective and physician-recorded assessments will be used to classify the patient's burden of AF as mild, moderate, or severe, Conclusion: Rigorous yet practical approaches are needed to allow for a comprehensive understanding of quality of life in patients with AF, The international study design outlined in this review article represents an attempt to systematically address quality of life in patients with AF and may serve as an example of the types of measures that may be useful in assessing quality of life in patients with AF.