S-PLUS Workbench: An Integrated Development Environment for S Programmers David A. Henderson and Stephen P. Kaluzny, Insightful Coporation The Enterprise Developer version of S-PLUS 8.0 contains several features to increase the productivity of an S language programmer. These features are found in the S-PLUS Workbench which is a plugin perspective for the open source Eclipse Integrated Development Environment. Eclipse allows integration with several source control solutions, such as Subversion and CVS, which are accessible from within the S-PLUS perspective using menu selections. The S-PLUS perspective also contains a debugger, using a Java syntax parser, and profiler with the ability to set breakpoints within S code and the ability to monitor memory usage at set points within the script code. The perspective contains an integrated command line console and any graphs produced are embedded within Eclipse as their own pane with tabs in the case of multiple graphs. An example of how the S-PLUS Workbench can increase productivity in creating and deploying S code will be demonstrated with a demo.