Traditionally software is loaded onto, or downloaded to, a user’s PC where it is then executed. The ubiquitous Web, however, allows another choice, a Web front end for data collection residing on the user’s PC, a Web service which runs on a remote server, and Web delivery of service output back to the user’s PC. We are used to seeing this latter architecture used for information retrieval and simple ecommerce transactions, but the same architecture can also be used for more complicated services. We present two case studies where we developed complex Web-enabled services that are currently being used by clients over the public Internet. From a software-engineering standpoint, we explain the compelling reasons for developing these applications using this architecture and the advantages we experienced over traditional methods. We also highlight some of the trials of developing, testing, marketing, and maintaining such complex Webenabled services.