Abstract:This paper describes a conceptual framework for building expert systems in repair domains. A specific example of the use of this framework in building an expert system for a field service repair problem is given. The example system is designed to assist field service technicians in troubleshooting and repairing electronic systems at the board level. This system, a Field Service Advisor (Fieldserve), is designed (1) to diagnose single or multiple defects in electronic systems, (2) to guide a technician through appropriate repair procedures, (3) to verify diagnoses and monitor repair effectiveness and (4) to maintain records for subsequent evaluation and quality control.