Thanks, that looks like the ticket. And your assumptions are correct - HTML parsers, um, no thank you. The input happens to be HTML, but it's very simple, fairly fixed format, and the problem could just as easily be expressed without HTML tags. And I'm hoping to wrap it all up in a map() (lots of data to iterate over) so it's much neater.

Now, off to spend more time staring hard at the solution until its lessons burn themselves deep into my brain.

thanks

the hatter