Web Service (WS) technology represents a fundamental shift in the way web applications are developed for e-business. It is becoming the next paradigm to deploy business services on the Web. Developing WS is a new challenge due to the complexity of various business processes and different communication protocols. In this paper, we propose a methodology to efficiently develop Web Services by wrapping software agents. This agent oriented method uses software agents as building blocks of WS, and exploits the commonly available agent development tools to accelerate the whole development cycle. Software agents in this methodology not only implement the business processes, but also enrich the functions of WS. Our approach provides a solution for Web Service engineering. A case study in holiday booking service is presented to show the benefits and advantages of this agent oriented service engineering methodology.