Download XML ValidatorBuddy to run your Schematron rules:
XML Validator Buddy provides a complete ISO Schematron environment including a special editor and validator to create and test rules in less time. Schematron is a semantic language which is often used to express high-level business rules and to provide an additional layer on testing XML data. A Schematron schema is also written in XML and uses a small number of elements. Single tests are evaluated as XPath expressions.
Schematron is easy to learn and capable of expressing constraints that other XML languages like XSD and DTD cannot. In general, anything that can be evaluated as an XPath statement, can be part of a rule. For example, Schematron can require that the validation status of an element depends on the content of one of its siblings. Or it can request or require that an element must have specific attributes. With Schematron you can also validate required relationships between multiple XML documents.