As most current electronic contract management systems work well for only a few but not all processes in a contract lifecycle because of their inabilities to handle electronic documents in more than one file format simultaneously. In this paper, we present an efficient and automated enterprise electronic contract management system using both XML and secure PDF documents. The advantages of such dual file formats are to provide the best capabilities and functionalities for contract creation, negotiation, execution and data mining. The structured XML document allows an easy and flexible way to create, negotiate, revise and finalize a contract while the PDF document permits adding signature as watermark on a secure signed contract. A novel conversion method to convert between these two file formats is also described.