HEARTS (Hospital Evaluation Assistant for Rapid Transplant Screening) is a knowledge based system (KBS) which conducts initial screening to determine if patients with coronary artery disease may be placed on the waiting list for a heart transplant. Given the critical shortage of donor organs, the medical community can only place patients who are likely to benefit from an organ transplant on the waiting list. Unfortunately, the process for screening patients is lengthy, approximately 4 months. During this time a donor organ may become available, but those patients still being screened cannot be considered as a possible match. We describe the development, testing, and user response to HEARTS. HEARTS benefits patients by speeding the screening process and placing them on the waiting list more quickly. Members of a transplant committee benefit by being freed from conducting the initial screening to focus on more critical issues.