An post-WWII outgrowth of twelve-tone music, from an Olivier Messiaen idea. Rather than just systemically
organize the individual pitches, a serial composer would use a similar
method to organize the durations, dynamics, or octave of each note. "Total serialism" meant that every element was handled this way. Sort of a dead end, but one which influenced escape routes such as systems music, aleatory forms of composition (like John Cage's "chance music"), and fractal music.