\relative c'' {
  % Multi-measure rests by default are set under the fourth line
  R1
  % They can be moved using an override
  \override MultiMeasureRest.staff-position = #-2
  R1
  \override MultiMeasureRest.staff-position = #0
  R1
  \override MultiMeasureRest.staff-position = #2
  R1
  \override MultiMeasureRest.staff-position = #3
  R1
  \override MultiMeasureRest.staff-position = #6
  R1
  \revert MultiMeasureRest.staff-position
  \break

  % In two Voices, odd-numbered voices are under the top line
  << { R1 } \\ { a1 } >>
  % Even-numbered voices are under the bottom line
  << { a1 } \\ { R1 } >>
  % Multi-measure rests in both voices remain separate
  << { R1 } \\ { R1 } >>

  % Separating multi-measure rests in more than two voices
  % requires an override
  << { R1 } \\ { R1 } \\
     \once \override MultiMeasureRest.staff-position = #0
     { R1 }
  >>

  % Using compressed bars in multiple voices requires another override
  % in all voices to avoid multiple instances being printed
  \compressMMRests
  <<
   \revert MultiMeasureRest.direction
    { R1*3 }
    \\
   \revert MultiMeasureRest.direction
    { R1*3 }
  >>
}