In this report we present an extension O M Doc to the OpenMath standard that allows to represent the semantics and structure of various kinds of mathematical documents, including articles, textbooks, interactive books, courses. It can serve as the content language for agent communication of mathematical services on a mathematical software bus. We motivate and describe the O M Doc language and present an Xml document type definition for it. Furthermore, we discuss applications and tool support. Status of this document: This document describes version 1.0 of the O M Doc format, released November 1. 2000. Version 1.0 is the result of using O M Doc in various experiements and projects, stabilizes these experiences to serve as a basis for more sophisticated tools. The document type definition can be found at http: //www. mathweb.org/ omdoc/dtd/omdoc1.0. dtd . The O M Doc format will continue to evolve, the next steps are to include XML Schema support and more sophisticated (autho..