Diagnostic Yield Characterization Expert (DYCE) is a knowledge based system shell used for automated data interpretation in semiconductor manufacturing. Using a combination of artificial intelligence techniques, DYCE assists manufacturing and development personnel to diagnose problems by automatically interpreting hundreds of pieces of data, just as a human expert would do. Diagnosis time has been reduced from several hours to minutes. DYCE’s inference engine has generic meta-rules to represent the heuristic problem-solving knowledge of the experts; this permits the representation of hundreds of traditional expert system rules with a few dozen meta-rules. This generic shell architecture has important benefits in maintaining an expert system in a dynamic environment without the need for a knowledge engineer or AI training.