The chapter provides an updated overview of the epidemiology of peripheral artery disease (PAD), integrating new data with previous findings. It highlights that PAD is more common than previously thought, with a prevalence that rises sharply with age and is higher in men than in women, particularly for severe or symptomatic disease. Key risk factors for PAD include smoking, diabetes mellitus, hypertension, dyslipidemia, and chronic kidney disease. The chapter also discusses the limitations of current diagnostic methods, such as the ankle-brachial index (ABI), and the importance of considering multiple risk factors in statistical models to accurately estimate their unique contributions. Additionally, it explores the role of genetic factors and other potential risk factors, such as psychosocial factors and oral health. The chapter concludes by discussing PAD risk scoring systems and the progression of PAD, emphasizing the need for further research to understand the early natural history of the disease.The chapter provides an updated overview of the epidemiology of peripheral artery disease (PAD), integrating new data with previous findings. It highlights that PAD is more common than previously thought, with a prevalence that rises sharply with age and is higher in men than in women, particularly for severe or symptomatic disease. Key risk factors for PAD include smoking, diabetes mellitus, hypertension, dyslipidemia, and chronic kidney disease. The chapter also discusses the limitations of current diagnostic methods, such as the ankle-brachial index (ABI), and the importance of considering multiple risk factors in statistical models to accurately estimate their unique contributions. Additionally, it explores the role of genetic factors and other potential risk factors, such as psychosocial factors and oral health. The chapter concludes by discussing PAD risk scoring systems and the progression of PAD, emphasizing the need for further research to understand the early natural history of the disease.