The music of many cultures is characterized by lengthy musical repetitions, especially where ceremony, text and dance determine the amount of music needed. In Western Classical music, formal repetition is an especially prominent feature. Considering the number of pieces in the customary concert repertoire which include repeats, even the casual observer may be surprised to see only a dozen column inches devoted to the topic in The New Grove Dictionary of 1980, with only five bibliographical references, all to peripheral sources. The dictionary entry is, however, well focused, with examples to support its general theme that ‘the evolution of the notation, its exact interpretation and the practice of making repeats .. raise certain problems, not all of which have obvious solutions’.