I stand corrected. Thanks, itub and Roy Johnson. Normally I do this in two phases (the match, then the substitution), but that's just me, and not something to advocate as the One True Perl Way. :-) I just find it makes more sense, but largely because I forget about s returning the number of matches, which is largely due to lack of need (usually I do the substitution and continue without any branching on whether it was succesful or not).