Intracranial artery stenosis (ICAS) is a major cause of ischemic stroke. The presence and progression of atherosclerosis in the intracranial arteries is the underlying pathophysiology. However, it is also known that there are racial differences in the prevalence of ICAS, and that the presence of comorbidities such as hypertension, dyslipidemia, and diabetes mellitus are the risk factors. Advances in diagnostic and imaging techniques have increased the opportunities to diagnose and treat mild to moderate or even asymptomatic ICAS patients. In order to provide appropriate management and treatment to prevent future severe strokes, better understanding of their clinical characteristics is needed, and knowledge of the current clinical evidence regarding the optimal treatment strategy is also essential. Here, we have reviewed these aspects for a better understanding of the treatment for ICAS. Endovascular approach is one of the major treatment strategies for ICAS. Although the clinical indications for endovascular treatment (EVT) remain controversial, it is important to recognize that there are some cases that require EVT due to refractoriness to aggressive medical approaches for severe symptomatic ICAS. This chapter outlines the techniques, devices, and perioperative management of EVT, and presents some clinical cases that have been successfully treated with EVT for severe ICAS. Although EVT for ICAS is not yet an evidence-based standard of treatment, there are patients who may benefit from this approach. Further accumulation of clinical cases and well-designed randomized controlled trials (RCTs) including such cases are essential to establish the efficacy and safety of EVT for ICAS.