Discussions of rock or contemporary popular music are very often suffused with suggestions of massive and remarkable ‘change’ (in musical style, in surrounding fashions, etc.). Just as often, however, they are filled with virtually opposite visions of endless repetition, or continual ‘sameness’ (the music all merely sounding alike). Diverging in this way, views of change in popular music tend towards extreme polarisation – so much evidently depending upon the scale and scope of comparison, and indeed much of the problem centring on the domain or level in music isolated as the one most likely to offer explanation of the underlying processes.