Because of the increasing discrepancy between the number of identified candidates for heart transplantation and available donor organs, appropriate selection of patients for heart transplantation is critical. The establishment of a cardiac prognosis that is significantly worse than that following heart transplant is central in the determination of candidacy for transplantation. However, with recent improvements in heart failure management, prognosis must be considered a dynamic state involving periodic reassessment to ensure an individual's ongoing suitability for transplantation. There have been many descriptions of prognostic indexes in heart failure, but care must be used when extrapolating observations collected from patients with a broad range of conditions to those with end-stage disease. The contraindications to heart transplantation have also evolved with the increasing success of the transplant process. Many conditions that precluded patients from heart transplant in the past are no longer regarded as absolute. Despite less stringent conditions for recipient candidacy, the need to achieve optimal results with an increasingly valuable donor resource will necessitate careful scrutiny of the posttransplant implications of the various conditions currently regarded as contraindications to heart transplant. Determination of heart transplantation candidacy therefore continues to remain a highly individualized process, requiring clinical judgment and experience.