If you're trying to test if the user does NOT have a particular role, you can use:

not(in/user/roles/role = 'Trade')

Thank you Steve

I just tried this and it did not exlude trade users. We have 2 customer types Everyday customers and Trade customers.

We have given trade the Trade role

We do not want our everydau customers to see the Shipping methods that are for Trade

Here is the full Availability code to exclude Trade Customers.   It it still showing for reguiar and trade. 

<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:template match="/">
    <out>
      <allowed>
        <xsl:choose>
          <!--                                                                                                   Test if Australia
                                                                                                  -->
          <xsl:when test="not(in/user/roles/role = 'Trade') and in/salesOrder/subTotalAmount &gt; 27.27 and in/salesOrder/shippingCountryCode = 'AU' and in/salesOrder/shippingSubdivisionCode = 'AU-SA' and (in/salesOrder/shippingPostalCode = '5000' or in/salesOrder/shippingPostalCode = '5006')">true</xsl:when>
          <xsl:otherwise>false</xsl:otherwise>
        </xsl:choose>
      </allowed>
    </out>
  </xsl:template>
</xsl:transform>

Hi Steve

I have it working  not(in/user/roles[role  = 'Trade'])   I had to add the [] Brackets like the original.

Thank you your sugguestion got me to the right solution