Web services, a recent development in web technology, enables programs (services) on the World Wide Web (WWW) to communicate with each other. A program (web service) available on the WWW has to be robust to serve the vast number of users on the WWW and should have high level of availability. This can be achieved by incorporating fault-tolerance in a program by having multiple instances of the same program running on different servers. This book presents a system to start, administer and monitor multiple instances of a web service on different servers. The system designed to incorporate fault- tolerance in web services cannot affort to have a single point of failure. Hence, the system itself is designed to be fault-tolerant. This book also presents a Web Service Registry that provides a means for the developers to register their web services with the Web Service Registry and thus, make the web services discoverable and accessible to the world.