Since the advent of XML as a meta language for data exchange on the Internet, numerous e-business standards for various applications and business domains have been developed. The problem is that such e-business standards can get very complex with regard to the size of respective formal specifications as well as supplementing documentations. The latter provide important information required for understanding and eventually correctly adopting such as standard. We address this problem from a document engineering perspective which provides means for specifying, designing, and implementing electronic documents. In particular, we employ the technique of XML schema annotations which allow for closely integrating both the formal specification and its supplementing documentation. We show the usefulness of our proposal by reporting on experiences made in an e-business standardization project.