Without showing us the input form you are making us guess....
<xsl:starts-with(Module, $sModule)>
there is no xsl:starts-with element, so that will be a synatx error.
You want something like
<xsl:template match="/">
<xsl:for-each select=Sales/Summary[starts-with(Module,$sModule)]">
<xsl:sort select....
assuming Module is a child of Summary
--
http://www.dcarlisle.demon.co.uk/matthew
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