This invention relates to a method and apparatus in an interactive voice response system for caching VoiceXML documents. A method and system for processing a VoiceXML document prior to interpretation by a browser comprises: receiving a document from a web server; constructing a document object model (DOM) of the constituent parts of the document for interpretation by a browser; storing the DOM and the constituents parts in cache memory whereby next time the DOM and parts are required for interpretation it is retrieved from cache memory rather than constructed again from the source code. The constituent parts may be re-used in the or other documents. The constituent parts are separated into logic and data parts.