Hi, I was looking at trying to implement something similar to amsmath's intertext command. I can get the basic functionality working as follows. \def\startintertext#1\stopintertext{% \noalign{#1}\NR} \startformula \startalign \NC A_1 \NC= \left| \int_0^1 (x^2 - 3x)\, dx \right| + \left| \int_1^2 (x^2 -5x + 6)\, dx \right| \NR \startintertext Take limis of both integrals %\input tufte \stopintertext \NC \NC = \left| \frac{x^3}{3} - \frac{3}{2} x^2 \right|_0^1 + \left| \frac {x ^3}{3} - 7 \frac{5}{2} x^2 + 6x \right|_1^2 \NR \NC \NC = \left| - \frac{7}{6} \right| + \left|\frac{14}{3} - \frac{23}{6}\right| = \frac{7}{6} + \frac{5}{6} = 2 \NR \stopalign \stopformula This seems to be working fine. However, \intertext defined in amsmath.sty seems to be doing a lot more (I just can't figure out what it is doing?) Can someone suggest how to make the above command more robust on the lines of \intertext? %----- from amsmath.sty ------------- \def\intertext@{% \def\intertext##1{% \ifvmode\else\\\@empty\fi \noalign{% \penalty\postdisplaypenalty\vskip\belowdisplayskip \vbox{\normalbaselines \ifdim\linewidth=\columnwidth \else \parshape\@ne \@totalleftmargin \linewidth \fi \noindent##1\par}% \penalty\predisplaypenalty\vskip\abovedisplayskip% }% }} Thanks, Aditya -- Aditya Mahajan, EECS Systems, University of Michigan http://www.eecs.umich.edu/~adityam || Ph: 7342624008