From http://www.w3schools.com (Copyright Refsnes Data)

XSL-FO and XSLT

XSL-FO and XSLT can help each other.

Remember this Example?

<fo:block
    font-size="14pt" font-family="verdana" color="red"
    space-before="5mm" space-after="5mm">
W3Schools
</fo:block>

<fo:block
    text-indent="5mm"
    font-family="verdana" font-size="12pt"
    space-before="5mm" space-after="5mm">
At W3Schools you will find all the Web-building tutorials you
need, from basic HTML and XHTML to advanced XML, XSL, Multimedia
and WAP.
</fo:block>

Result:

W3Schools

At W3Schools you will find all the Web-building tutorials you need, from basic HTML and XHTML to advanced XML, XSL, Multimedia and WAP.

The example above is from the chapter about XSL-FO Blocks.

With a Little Help from XSLT

Remove the XSL-FO information from the document:

<header>
W3Schools
</header>

<paragraph>
At W3Schools you will find all the Web-building tutorials you
need, from basic HTML and XHTML to advanced XML, XSL, Multimedia
and WAP.
</paragraph>

Add an XSLT transformation:

<xsl:template match="header">
<fo:block
    font-size="14pt" font-family="verdana" color="red"
    space-before="5mm" space-after="5mm">
    <xsl:apply-templates/>
</fo:block>
</xsl:template>

<xsl:template match="paragraph">
<fo:block
    text-indent="5mm"
    font-family="verdana" font-size="12pt"
    space-before="5mm" space-after="5mm">
    <xsl:apply-templates/>
</fo:block>
</xsl:template>

And the result will be the same:

W3Schools

At W3Schools you will find all the Web-building tutorials you need, from basic HTML and XHTML to advanced XML, XSL, Multimedia and WAP.