python XSV (XML Schema Validator) is an open source (GPLed) work-in-progress attempt at a conformant schema-aware processor, as defined by XML Schema Part 1: Structures, May 2, 2001 (REC) version. It has been developed at the Language Technology Group of the Human Communication Research Centre in the Division of Informatics at the University of Edinburgh, with support for one of us (Thompson) from the World Wide Web Consortium.