In a retrospective analysis on 323 orthotopic liver transplant procedures performed between July 1984 and October 1991 the incidence of two forms of primary dysfunction (PDF) of the liver: primary nonfunction (PNF), and initial poor function (IFF) were studied. The incidence of PDF was 22% (73/323) with 6% PNF (20/ 323) and 16% IPF (53/323), while 78% (250/323) had immediate function (IF). Occurrence of both IPF and PNF resulted in a higher graft failure rate (P49 years), extended preservation times (>18 hr), and fatty changes in the donor liver biopsy, as well as reduced-size livers, younger recipient age, and renal insufficiency prior to OLTx, significantly affected the incidence of IPF and PNF. Multivariate analysis of potential risk factors showed that reduced-size liver (P=0.0001), fatty changes on donor liver biopsy (P=0.001), older donor age (P=0.009), retransplantation (P=0.01), renal insufficiency (P=0.02), and prolonged cold ischemia times (P=0.02) were independently associated with a higher incidence of IPF and PNF. No statistical correlation was found between PDF and etiology of ESLD, nutritional status of the recipient, UNOS status, and Child-Pugh classification in this study. We conclude that PNF and IPF are both separate clinical entities that have a sig nificant effect on outcome after OLTx. Routine donor liver biopsies are recommended to decrease the rate of IPF and PNF. The combination of risk factors shown to be significant for PDF should be avoided—and, if that is not possible, the only variable that can be controlled, the preservation time, should be kept as short as possible.