XML is a communication format for exchanging structured documents and data. Too often, an XML format is chosen arbitrarily and on the fly during development, without much planning or design. Design the right XML format up front, and you can meet the needs of everyone involved in the communication. If you don't, you're in for a long journey of format revisions. <A HREF="http://www.ibm.com/developerworks/library/x-extensxml.html?ca=drs-">Learn how to design a format less likely to require change</A> and agile enough to incorporate new requirements with the simple addition of new extensions instead of full changes.