General Electric used case-based reasoning for gas turbine diagnostics at their monitoring and diagnostics center in Atlanta, GA. This application had requirements that included accuracy, maintainability, modularity, parameterization, robustness, and integration of the system into an existing infrastructure. The CBR system has a modular plug-and-play architecture to facilitate experimentation and optimization. It was integrated into the production environment in 2004. The CBR system is currently in a trial deployment where diagnoses made by the system are created along with the previous process of using human-generated diagnosis.