This study investigates the influence of the Austrian music theorist Heinrich Schenker on American music theory since 1940, including a survey of writings related to Schenker and theory textbooks displaying his influence. The Schenker influence on American music theory includes many journal articles on Schenker and his principal students. His methods are employed often in analytical discussions of various issues. In addition to numerous dissertations and theses written about Schenker, a number of textbooks are now based wholly or in part on his approach to musical understanding. The current trend towards accepting Schenker's theories is likely to continue as more people are exposed to his teachings.