Distributed content-based Publish/Subscribe is a messaging middleware paradigm that has been gaining traction in both the research and commercial communities. The simple interface and decoupled nature of publish/subscribe allows for powerful and flexible systems. Unfortunately, the majority of existing research focuses on limited application areas such as selective information dissemination. In this thesis, a new publish/subscribe system called PADRES developed for workflow management is presented, along with some of the interesting and novel features driven by this application. An analysis of the interactions between PADRES clients necessary to support a realistic middleware system is presented as a set of messaging patterns. An in-depth look at the requirement of accessing historic publications, along with a concrete methodology for satisfying and optimizing such queries is also included. Details about the implementation of these features in the PADRES system are provided.