W hile syncopation generally refers to any conflict between surface accents and underlying meter, in rock and other recent popular styles it takes a more specific form in which accented notes occur just before strong beats. Such “anticipatory” syncopations suggest that there is an underlying cognitive representation in which the accented notes and strong beats align. Syllabic stress is crucial to the identification of such syncopations; to facilitate this, we present a corpus of rock melodies annotated with lyrics and syllabic stress values. We propose a new measure of syncopation that incorporates syllabic stress; we also propose a measure of anticipatory syncopation, and show that it reveals a strong presence of this type of syncopation in rock music. We then use these measures to explore other aspects of syncopation in rock, including its occurrence in different parts of the 4/4 measure, its dependence on tempo, its historical evolution, and its aesthetic functions.