Methods and apparatus for the dynamic modification of parameters existing within computing systems are described. An application program runs a Graphical User Interface (GUI) having a navigator panel 152 and an edit panel 154. An XML textual file 160 is written to the application GUI 150 by Java code. The navigator panel 152 represents the XML file in a tree structure having groups of parameters. When a particular parameter is selected, it is caused to appear in the edit panel 154, where its attributes (textual) can be added or modified. The modified parameter is then persisted to a database 170.