Circular breathing is a technique that involves breathing in through the nose while simultaneously exhaling air through the mouth. This technique allows a wind instrumentalist to maintain a steady flow of air through the instrument for an extended amount of time. Employed correctly, the performer can play longer phrases without running out of air. Historically, this technique has been used by glassblowers and eventually begun to be used by musicians. Although this breathing technique has not been well disseminated and well understood among musicians, it can be incredibly useful for any wind instrumentalist. Contemporary repertoire employs it more and more often, and it is becoming a necessary tool to have in our performance toolbox.