Web service is a growing technology that has been widely adopted by many organizations. It has provided a medium for communication between service provider and service requestor in the business environment. The role of semantic in web service has played an important role in this communication by allowing automatic discovery, selection and composition between the service provider and requestor. However, both service provider and the requestor are unable to achieve their business goals when there are miscommunications between their processes. This paper presents an overview of the process incompatibility between Web Services and the ways to automatically resolve them. Several approaches have been analyzed to understand the existing process mediation framework. These approaches have been presented in three categories namely Rule-based, Pattern-based and Plannerbased. Moreover, we have compared these approaches based on few criteria such as expressiveness, automation, correctness and completeness.