JavaScript XMLHttpRequest responseXML Property

Once an XMLHttpRequest has been initiated, sent and a response received, the XMLHttpRequest will have a responseXML property, if an XML document is received from the server. This property contains the response received from the server that can be processed by JavaScript as XML. DOM methods can by applied through JavaScript on the XML. If the server does not send back XML or if the XML is not well-formed the responseXML property will contain null.

Please see my Simple Ajax Example Tutorial with ColdFusion to see a practical application of this property.