This chapter provides a summary of the landmark surgical study known as the NASCET trial, which compared surgical versus nonsurgical treatment for patients with symptomatic carotid stenosis. The chapter describes the basics of the study, including funding, year study began, year study was published, study location, who was studied, who was excluded, how many patients, study design, study intervention, follow-up, endpoints, results, and criticism and limitations. The chapter briefly reviews other relevant studies and information, gives a summary and discusses implications, and concludes with a relevant clinical case regarding vascular surgery.