I changed Paul's solution with "hideNotes" to use rests instead of notes, to avoid the warning for clashing note columns. Aaron's solution works well for the score, but my problem came up when I tried to write the individual parts. The updated example below illustrates the problem and my solution to it. Thanks both of you!
\version "2.18.2" rit = \markup {\italic "rit." } atempo = \markup {\italic "a tempo" } tempos = { s2^\atempo s2^\rit \once \textLengthOn s2^\atempo s2^\rit } othertempos = { \hideNotes{r8^\atempo r r r} s2^\rit \hideNotes{r8^\atempo r r r} s2^\rit } notes = \relative c'{ c2. d8 b c2. g8 b } othernotes = \relative c'{ e8 f g a g2 c2 b } %solution with textLengthOn \score { << \new Staff <<\tempos \notes >> \new Staff {\othernotes} >> } \score { \new Staff <<\tempos \notes>> } \score { \new Staff <<\tempos \othernotes>> } %solution with hidden rests \score { << \new Staff <<\othertempos \notes >> \new Staff {\othernotes} >> } \score { \new Staff <<\othertempos \notes>> } \score { \new Staff <<\othertempos \othernotes>> } Erika