Methods and computer-readable media are provided for assisting with the creation of an extensible markup language (“XML”) path language (“XPath”) expression. According to one aspect, an application program for editing XSLT stylesheets provides a user interface that assists with the creation and editing of XPath expressions. When an XPath expression is being created, a user interface is displayed that includes the valid XPath tokens for the expression being created. As characters are entered into the expression, the valid XPath tokens are continually identified for the expression and the contents of the user interface control are updated. If one of the items displayed in the user interface control is selected, the XPath token corresponding to the selected item is inserted into the XPath expression.