Arteriovenous fistulas (AVFs) are abnormal communications with shunting of blood from an artery to a vein. AVFs mainly involve the peripheral vascular system but can affect virtually any organ or system in the body. They may be congenital, created surgically for hemodialysis, or caused by pathologic processes. This review describes the diverse origins of AVFs and illustrates the spectrum of imaging findings at radiography, ultrasound, CT, MRI, and digital angiography for AVFs in different locations: the CNS, thorax, abdomen, musculoskeletal system, and peripheral vascular system. We also discuss syndromes associated with AVFs and describe recent interventional techniques for treating AVFs.Familiarity with the spectrum of imaging findings in AVFs is essential for the accurate interpretation of images and facilitates diagnosis and therapeutic management. Radiologists can play a critical role in the diagnosis and treatment of AVFs. Digital angiography is helpful in elaborating a vascular map for endovascular treatment.