XXE, for short, is a full-fledged XML 1.0 editor featuring a word processor-like view (CSS2 styled). It has been created to make technical persons comfortable and productive at editing XML documents and XML data. [Open Source]

XML editor and validator of XML documents, DTDs, Relax NG Schemas and XML Schemas. Provides XSLT transformation and preview in built-in browser. Unicode support [Commercial]

Environment for authoring, editing, and testing XSLT style sheets, XML documents, DTDs, and XPATHs (Cooktop is no longer being developed - Last Update 2002) [Freeware]

An addon for GNU Emacs that uses Relax NG as its schema language and allows continuous validation and completion. Overview, download, mailing list, and links to support information.

Text-based non-validating XML editor for Windows, UNIX [Freeware]

Text-based XML editor for the Windows platform. It includes a built-in XML wellformedness tester and DTD validator. [Open Source]

A XML editor with syntax highlighting and customizable source view. Supports code-templates and auto complete. Ability to add, edit and delete Elements, Attributes, Text, CDATA sections, Comments, and Processing Instruction. This program does not yet ...

The Antenna House XML Editor 3.2 is a software application that combines two tools. One is for editing XML documents. The other is a parsing application, which verifies if an XML document and DTD is correct by comparing it with the XML specification. ...

A validating XML text editor for Windows that supports XML, XSL, DTD, CSS, and HTML files. [Shareware]

Validating XML/SGML document editor for Windows, Linux, and Solaris. [Freeware - soon to be Open Source]