Hi all, I am trying to line up some equations on a page and I'd like to insert some whitespace that has the same width as a -ve sign in an equation. An example would be trying to ensure the cosine and sine and on the first and second rows (second column) in the matrix below: \startpmatrix % Row 1 \NC - \cos \theta_{\text{el}} \, \sin \theta_{\text{az}} \NC \cos \theta_{\text{az}} \NC \sin \theta_{\text{el}} \, \sin \theta_{\text{el}} \NR % Row 2 \NC - \cos \theta_{\text{el}} \, \cos \theta_{\text{az}} \NC - \sin \theta_{\text{az}} \NC \sin \theta_{\text{el}} \, \cos \theta_{\text{el}} \NR % Row 3 \NC - \sin \theta_{\text{el}} \NC 0 \NC \cos \theta_{\text{el}} \NR \stoppmatrix Any ideas? Thanks, Graham