Summary: Complex graphical user interfaces (GUIs) that support a large amount of user interaction require a fast response time, a rich set of building blocks for an esthetic look-and-feel, and a development environment that supports ongoing change. On the World Wide Web, client-side technologies offer more of these features than do server-side solutions. Java and JavaScript are the two most popular languages used for client-side GUI implementations. Java implementations require a user to download a plug-in that contains a virtual machine to execute the Java byte-code. The installation and maintenance of this plug-in is sometimes an unsurmountable barrier to using Java. JavaScript lacks some of the desirable features of Java, such as easy to use object-oriented features and having a GUI class library, but does not require a plug-in. We have enhanced JavaScript by implementing a new language Object-JavaScript (OJS) and by providing an OJS library of GUI components, thus making it a viable alternative to Java.