In this paper we present an approach to allow monitoring of XML documents on the World Wide Web. We describe a distributed information monitoring architecture based on monitor rules. The architecture preserves the autonomy of the participating documents and allows evolution of the system by adding, removing and modifying XML documents. In order to illustrate the approach we present an example in the financial domain. KEY WORDS: Information monitor, information resources, monitor rules, conditions, actions, XML, World Wide Web. ________________________________________________________________________________