I've been reading about this for the last half hour, and here's what I understand: IE 6 will render a page in standards mode if there's a valid DTD, but not if there are any comments above the DTD. The XML declaration is a comment that goes above the DTD. If the XML declaration is wrapped in a conditional comment, the page will render in IE 6 in quirks mode but be invalid XHTML. Are there any workarounds to getting valid XHTML with an XML declaration to render in standards mode in IE6? If not, what are the disadvantages of removing the XML declaration entirely? Thanks.