I have a list of several dozens cities in XML format organized in no particular order such as this:

<cities>
<city>
<cityName>San Francisco</cityName>
<stateName>California</stateName>
</city>

<city>
<cityName>Charlotte</cityName>
<stateName>North Carolina</stateName>
</city>

...
</cities>


By using XSLT I want to organize in alphabetic order by states and by cities within each state, the state name should appear only once on top of cities located within every particular state.

State name a
  City name A
  City name B
  City name C
  ...

State name b
  City name A
  City name B
  City name C
  City name D
  ...
...

I tried this:

<xsl:apply-templates select="cities/city">
<xsl:sort select="stateName" />
<xsl:sort select="cityName" />
</xsl:apply-templates>

<xsl:template match="city">

<xsl:if test="preceding-sibling::*[1]/stateName != stateName" >
<xsl:value-of select="stateName" />
</xsl:if>
<xsl:value-of select="cityName" />
</xsl:template>

The problem is that once I execute this all cities are preceded by a stateName.

Thanks for helping me.
Juan

I put all the stuff in the "root template", though it will be better to break it down to several templates:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:template match="/">
        <xsl:variable name="set-of-states" select="/cities/city/stateName[not(. = preceding::stateName)]"/>
        <xsl:for-each select="$set-of-states">
            <xsl:sort select="."/>
            <br/>
            [<xsl:value-of select="."/>]<br/>
            <xsl:for-each select="/cities/city/cityName[../stateName = current()]">
                <xsl:sort select="."/>
                <xsl:value-of select="."/><br/>
            </xsl:for-each>
        </xsl:for-each>
    </xsl:template>
</xsl:stylesheet>

Armmarti
many, many thanks for your answer, it worked and I'm really happy, thanks to you.

I wish you a really good week!

Thanks
Juan

You are welcome POL