Introduction -- Eleven-pitch-class tonality -- The modal gamut in the sixteenth century -- Tonality and systems in the seventeenth and early eighteenth centuries -- Tonality and systems in the mid- to late-eighteenth century : the classical ideal -- Nineteenth-century approaches to eleven-pitch-class systems derived from the Viennese classical tradition -- Eleven-pitch-class systems in the music of mid- to late-nineteenth-century romantic composers -- The romantic avant garde and the rumblings of modernism.